Food Chemistry
Zeinab Nooshi Manjili; Alireza Sadeghi Mahoonak; Vahid Erfani Moghadam; Mohammad Ghorbani; Hoda Shahiri Tabarestani
Abstract
IntroductionSeeds and nuts have received increasing attention due to their nutritional value and the high therapeutic properties of their bioactive compounds. Most of the seeds are used as nuts, and some of them are considered agricultural waste. Pumpkin seeds have a high content of protein (30–40% ...
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IntroductionSeeds and nuts have received increasing attention due to their nutritional value and the high therapeutic properties of their bioactive compounds. Most of the seeds are used as nuts, and some of them are considered agricultural waste. Pumpkin seeds have a high content of protein (30–40% in terms of dry matter). Proteins are among the vital health-giving components that provide nitrogen, essential amino acids and energy needed by the body. Pumpkin seeds are a good source of amino acids such as valine, histidine, isoleucine, leucine, threonine and methionine. Protein hydrolysate is a mixture of peptides and amino acids that can show antioxidant, antimicrobial, anticancer, antidiabetic and antihypertensive properties. During hydrolysis, proteins are broken into small peptides and amino acids. Since enzymatic hydrolysis is performed in relatively mild conditions and no amino acid damage occurs, this type of hydrolysis is preferred over acid and alkaline hydrolysis. Hydrolysates obtained from pumpkin seed protein have bioactive properties, especially antioxidant activity. Pretreatment of proteins before enzymatic hydrolysis works to improve the release of bioactive peptides from different proteins. Pretreatment causes the three-dimensional structure of the protein to open and helps increase the access of enzymes to peptide bonds. The main properties of microwaves usually show three characteristics: penetration, reflection and absorption. Enzymatic hydrolysis with the help of microwaves can shorten the time of enzymatic hydrolysis and improve the speed of the reaction. The purpose of this research is to investigate the antioxidant activity of pumpkin seed protein hydrolysates (Cucurbita maxima L.) by the alcalase enzyme in two conditions: without pretreatment and using microwave pretreatment.Material and methodsIn this study, Pumpkin fruit (Cucurbita maxima L.) was purchased from the local market of Astane Ashrafieh in Gilan province, and after separating the seeds manually, they were dried in an oven at 50°C for 72 hours. After the production of protein concentrate from pumpkin seeds, the chemical properties of the concentrate, such as the amount of fat, protein, ash and moisture, were measured. The isolated pumpkin seed solution was exposed to microwave energy with a power of 450–900 watts for 30–90 seconds and was used as a substrate solution in enzymatic hydrolysis experiments. It should be noted that after measuring the total antioxidant power for different powers and times of microwave pretreatment, the power of 600 watts was selected for 30 seconds and applied before enzymatic hydrolysis. Enzymatic hydrolysis was done by the alcalase enzyme with a concentration of 0.5 to 2.5% compared to the protein substrate during a time period of 20 to 190 minutes, and the optimum temperature and pH of alcalase were determined in order to produce hydrolysates with antioxidant activity. Antioxidant power was measured by using DPPH free radical inhibition, total antioxidant activity and iron chelation activity methods.Result and discussionBioactive peptides produced by the enzymatic hydrolysis of proteins have significant antioxidant properties. Pumpkin seeds can be used as a rich source of nutrients and bioactive compounds in various food industries. The results showed that the maximum amount of antioxidant activity without pre-treatment was achieved in 165 minutes with a 2.2% ratio of E/S by using DPPH free radical scavenging activity (40.5%), total antioxidant power (0.79), and iron chelation activity (96.2%) methods. By using microwave pre-treatment, the maximum amount of antioxidant activity was achieved in a shorter time and with less enzyme (105 minutes and E/S ratio 1.5%) using DPPH free radical scavenging (52%), total antioxidant power (0.711), and iron chelation activity (93%). Therefore, it can be concluded that using enzymatic hydrolysis by microwave pre-treatment, in addition to achieving hydrolysates with proper antioxidant activity, is a suitable method to save time and reduce enzyme concentrations used in enzymatic hydrolysis.
Food Chemistry
Iysan Izanloo; Alireza Sadeghi Mahoonak
Abstract
Introduction Free radicals originate from oxidation reactions decrease food quality and also promote incidence of various diseases such as cancer. In this regard, the use of natural compounds with antioxidant properties, such as bioactive peptides, is of interest to many researchers. Food-derived ...
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Introduction Free radicals originate from oxidation reactions decrease food quality and also promote incidence of various diseases such as cancer. In this regard, the use of natural compounds with antioxidant properties, such as bioactive peptides, is of interest to many researchers. Food-derived bioactive peptides, can play an important role in the oxidative systems. Ultrasound, as a cheap and green technology, is widely used to extract proteins and antioxidant compounds. Ultrasound pretreatment before enzymatic hydrolysis can open the protein structure and increase the intensity of proteolysis by increasing the exposure of peptide bonds prone to enzymatic hydrolysis; which increases the production efficiency of bioactive peptides. Ultrasound treatment changes the three-dimensional structure of proteins. Therefore, a combination of pretreatment with ultrasound and sequential enzymatic hydrolysis can be a promising way to modify the function of proteins. Materials and Methods In this research the effect of hydrolysis time and ultrasonic pretreatment on enzymatic hydrolysis of edible mushroom protein by pancreatic enzyme to produce peptides with high antioxidant capacity was evaluated. First edible mushroom was turned into powder and then, in order to optimize the production of hydrolyzed proteins with maximum antioxidant activity, the hydrolysis was performed 30, 60, 90, 120, 150, 180 and 210 minutes with a ratio of enzyme to substrate of 1% (based on the result of previous research) and at 40°C in four conditions (1- without ultrasound pre-treatment, 2- with ultrasound pre-treatment with 40% power, 3- with ultrasound pre-treatment with 70% power and 4- with ultrasound pre-treatment with 100% power) by ultrasound probe in 5 minutes before adding the enzyme. In the next step, the antioxidant capacity of hydrolyzed proteins was measured at different times by DPPH free radical scavenging activity, iron ion reduction power, iron ion chelation and total antioxidant capacity. Results The results showed that the highest DPPH free radical scavenging activity in untreated and treated samples with 40, 70 and 100% ultrasound power were 69.1, 77.45, 79.07 and 80.27, respectively. In most of the hydrolysis times, DPPH free radical scavenging activity in ultrasound treatment with 100% power was higher than the samples treated with 40 and 70% power. The highest total antioxidant capacity in untreated and treated samples with 40, 70 and 100% ultrasound power were 0.871, 1.025, 1.05 and 1.2 (absorption at 695 nm), respectively. In most of the hydrolysis times, the total antioxidant capacity in the samples treated with ultrasound with 100% power was higher than the samples treated with 40 and 70% power. The results showed that the highest reducing power of Fe3+ in untreated and treated samples with 40, 70 and 100% ultrasound power were 2.03, 2.40, 2.44 and 2.51(absorption at 700 nm), respectively. The highest iron ion chelation power in untreated and treated samples with 40, 70 and 100% ultrasound power were 25.22, 30.40, 26.52 and 41.10%, respectively. By increasing the ultrasound power in most of the hydrolysis times, the chelating power of iron ions in the ultrasound treatment with 100% power was higher than the samples pretreated with 40 and 70% power. The results showed that samples pretreated with 100% power ultrasound have the highest antioxidant properties compared to samples without pretreatment and pretreated with 40% and 70% ultrasound power. Based on the results, using ultrasound treatment with 100% power and during hydrolysis time of 60 minutes, a product with high antioxidant capacity was obtained and selected as a suitable treatment. Conclusion The ultrasonic mechanism is attributed to its thermal effects, cavitation and mechanical efficiency, so that it can increase the mass transfer and increase the contact between the substrate and the enzyme or change the spatial structure of the substrate. The results showed that samples pretreated with ultrasound with 100% power have the highest antioxidant properties compared to samples without pretreatment and pretreated with 40 and 70% power. Therefore, the use of high-power ultrasonic pretreatment shortens the hydrolysis time to achieve peptides with higher antioxidant capacity and thus increases the efficiency of enzymatic hydrolysis.
Food Chemistry
Maryam Rahimipanah; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Hoda Shahiri Tabarestani; Mohsen Nabimeybodi
Abstract
Introduction
High levels of free radicals can damage biomolecules and eventually cause oxidative stress. Bioactive peptides produced during enzymatic hydrolysis keep high health properties, such as antioxidant properties. The production of antioxidant peptides has received much attention as a ...
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Introduction
High levels of free radicals can damage biomolecules and eventually cause oxidative stress. Bioactive peptides produced during enzymatic hydrolysis keep high health properties, such as antioxidant properties. The production of antioxidant peptides has received much attention as a new generation of natural antioxidants. Plants are one of the most abundant sources of biopolymers, especially protein. As long as the protein structure is intact, its amino acid sequence is inactive; however, during proteolysis, fermentation, and gastrointestinal digestion, these amino acids are released as oligopeptides ordinally with less than 20 amino acids and below 10 kDa in molecular weight. These peptides are more digestible and can exhibit specific bioactive properties such antioxidant properties. In this regard, the use of food waste containing protein to produce bioactive peptides and increase their value has received increasing attention. Enzymatic hydrolysis can increase their functional properties by converting proteins into peptides without affecting their nutritional value. Pomegranate seed protein is a by-product of the pomegranate seed oil industry and can be a good source of bioactive peptides with antioxidant properties. According to our knowledge, there isn’t any data about the enzymatic hydrolysis of pomegranate seed protein for antioxidant peptides production. In this study, the optimal conditions for enzymatic hydrolysis of pomegranate seed protein with trypsin using the responses surface method and the effect of hydrolysis on protein structure were investigated.
Materials and Methods
In this study, the protein was extracted from pomegranate seed, and using trypsin the optimization of enzymatic hydrolysis conditions of protein was determined by Face-Centered Central Composite design, which is one of the responses surface design methods. The effect of independent variables including temperature (30 to 45 °C), time (30 to 180 minutes), and enzyme to substrate ratio (1 to 3 w/w) on DPPH free radical scavenging activity and Fe+3 reducing power as responses, was evaluated. Validation tests were performed for confirmation of the proposed values by software and the degree of hydrolysis of the samples was determined. In the next step, the unhydrolyzed and hydrolyzed protein was evaluated for molecular weight distribution and their surface hydrophobicity was compared. Finally, scanning electron microscopy images were used to confirm the hydrolysis process.
Results and Discussion
Under optimal conditions obtained from the response surface method (temperature: 37.6 °C, time: 136.55 minutes, and enzyme to substrate ratio: 2.2%), trypsin-derived hydrolyzate, showed DPPH free radical scavenging power: 87±0.89% and Fe+3 reduction power: 0.293±0.44. Under these conditions, the degree of hydrolysis was equal to 30.1±1%. The optimum conditions of hydrolysis were validated by RSM. The increase in the surface hydrophobicity of the protein after the hydrolysis process indicated the unfolding of the pomegranate seed protein chain and the exposure of its structure during the reaction. The electrophoretic profile of denatured pomegranate seed protein showed smaller peptide bands and lower band intensity, along with losing some of the peptide fractions after hydrolysis. so the efficacy of trypsin at cleaving the protein was confirmed. Evaluation of images obtained by scanning electron microscopy showed that unhydrolyzed protein had complex structures comprised of random sheets of different sizes and shapes and the protein degraded into small fragments and looser structure with many folds after enzyme hydrolysis, resulting in smaller particles compared with untreated samples with the same SEM parameters
Conclusion
Considering the consumer’s tendency toward functional foods and present concerns about the application of synthetic additives and according to the results, the hydrolyzed pomegranate seed protein prepared by trypsin shows good antioxidant capacity. In addition, there will be a reduction in waste generated by the pomegranate processing industry. Further studies will need for the isolation and identification of the specific peptides and amino acid sequences and the evaluation of their possible incorporation in food matrices.
Food Biotechnology
Sara Shahryari; Alireza Sadeghi; Maryam Ebrahimi; Alireza Sadeghi Mahoonak; Ali Mayedi
Abstract
[1]Introduction: Evaluation of antimicrobial and probiotic properties of the microbiota isolated from fermented pseudo-cereals is important in order to prepare adjunct and starter cultures. Probiotics are live and active microorganisms that, if used in sufficient numbers, help the microbial balance of ...
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[1]Introduction: Evaluation of antimicrobial and probiotic properties of the microbiota isolated from fermented pseudo-cereals is important in order to prepare adjunct and starter cultures. Probiotics are live and active microorganisms that, if used in sufficient numbers, help the microbial balance of the gastrointestinal tract and improve its function. Probiotics are also used as a substitute for antibiotics and synthetic preservatives in the prevention and treatment of complications of many infectious and pathogenic gastrointestinal pathogens. Probiotic microorganisms include lactic acid bacteria (LAB) and yeasts, and despite numerous reports on the probiotic properties of LAB, the probiotic properties of yeasts are less reported. Probiotic yeasts are organisms resistant to antibacterial compounds and effective against pathogens, which can rapidly increase their population in the gastrointestinal tract. These yeasts have several properties such as antimicrobial effects, resistance to acid and bile, binding to mucosal surfaces, inhibitory activity against pathogens and also the inability to transmit antibiotic resistance genes. In the present study, after isolation of the predominant yeast from buckwheat sourdough, the probiotic and antifungal properties of the isolate were investigated. Based on the literature review, no study has been presented to evaluate the probiotic and antifungal capabilities of yeasts isolated from buckwheat sourdough. Materials and Methods: In the present study, predominant yeast was isolated from buckwheat sourdough, and then it was identified using PCR. Subsequently, probiotic properties of the isolate including survival in present of low pH and bile salt, antibacterial effect, antibiotic susceptibility assay, aggregation, hydrophobicity, haemolytic activity as well as its antifungal activity against Aspergillus niger and Aspergillus flavus were studied. After spontaneous fermentation of buckwheat, predominant yeast was isolated using ten-fold dilution of the sourdough sample and its spread plating. The predominant isolate was identified through PCR amplification of a 650 bp target sequence from its ribosomal gene and sequencing of the PCR product. Then, survival of the yeast was determined at pH=2 and 0.3% bile salt as simulated gastrointestinal conditions. Subsequently, simultaneous culture of the yeast with some food-borne indicator bacteria in chromogenic media was used to investigate the inhibitory activity of the isolate against the studied bacteria. After that, resistance of the yeast isolate against the common antibiotics and some antimycotic agents was evaluated using disc method. Co-aggregation ability and hydrophobicity capability of the isolate were also determined based on the absorbance tests. In vitro safety of the yeast isolate was checked through its cultivation on blood agar containing sheep blood. Next stage, overlay bioassay was conducted to investigate antifungal effect of the yeast on the selected fungi. Finally, one way analysis of variance (ANOVA) with the least significant differences (LSD) post hock at p<0.05 was used for statistical analysis of the data. Results and Discussions: Sequencing results of the PCR products led to the identification of Pichia kudriavzevii as predominant yeast isolated from buckwheat sourdough. Survival rate of the isolate after treatment in simulated gastrointestinal conditions was 79.26% in comparison with the control. Antibacterial effect of the isolate on Escherichia coli was also significantly (P<0.05) higher than the other studied food-borne agents. Meanwhile, the growth of Listeria monocytogenes was decreased 19.50% in the present of the isolate. Whereas, the yeast isolate had no inhibitory effect on Salmonella enterica. Hydrophobicity and auto-aggregation capabilities of the isolate were also 64.07 and 67.40%, respectively. Furthermore, the isolate showed resistance towards all of the antibiotics tested, while it was resistant against ketoconazole and fluconazole, and the yeast was semi-sensitive towards itraconazole as antimycotic agents. The yeast isolate had no hemolytic activity, and its antifungal activity against A. niger and A. flavus was also verified. Accordingly, it is concluded that P. kudriavzevii isolate exhibits proper potential to be used as probiotic or protective culture in fermentation industries.In accordance with the results, probiotic characteristics of P. kudriavzevii (as the predominant yeast isolated from buckwheat sourdough) were approved. Accordingly, the isolate can be used as a potential probiotic culture in food industries.
Morteza Mohammadi; Mohammad Ghorbani; Alireza Sadeghi Mahoonak; Adel Beigbabaie; Samira Yeganeh zad
Abstract
Introduction: Phenolic compounds are known as a base of many functional foods due to their antioxidant properties and salutary effects. Phenolic compounds mainly found in plant sources. Agricultural wastes are one of the cheapest sources for getting phenolic compounds. Pistachio is considered one of ...
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Introduction: Phenolic compounds are known as a base of many functional foods due to their antioxidant properties and salutary effects. Phenolic compounds mainly found in plant sources. Agricultural wastes are one of the cheapest sources for getting phenolic compounds. Pistachio is considered one of the most important agricultural products in Iran. Study on the different parts of solid wastes generated from pistachio processing is worthy due to containing valuable compounds. On the other hand, using novel techniques such as supercritical CO2, subcritical water, pulsed electric fields, etc., have gained more attention in the past few years. These technologies do not have side effects on the raw materials and final products; do not use chemical solvents such as hexane, methanol, acetonitrile, etc., in comparison to traditional extraction methods with the long time needed and using chemical solvents with hazardous effect on consumers. In this study, the subcritical water extraction method as a green technology was used for the extraction of phenolic compounds from pistachio hull using y response surface methodology. Materials and Methods: In this study antioxidant properties of phenolic compounds extracted from pistachio hull by subcritical water fluid were evaluated. The extraction process is done at 120– 180 Celsius degree, pressure 10– 50 bar and ratio 1:10– 1:30 (sample to solvent) by using the subcritical water fluid method. The total phenolic compound, flavonoid compounds, reduction power, radical scavenging, and stability power of soybean edible oil were determined for each treatment. The stability power of extracts in soybean measured with rancimat test at 110 Celsius degree and airflow of 20 litter per minute. Comparison and statistical analysis for optimization of results accomplished using response surface methodology (RSM) by design expert software 7.0.0 version. After optimization, the results for optimum treatment were compared with BHT, ascorbic acid, and alpha-tocopherol. This comparison was done for reduction power, stability power, and radical scavenging ability. Results and Discussion: The results showed that the total phenolic compounds changed from 7671.43 to 8903.57 mg Gallic acid equivalent per 100 g dry matter. Reduction power increased by increasing temperature from 120 to 150 Celsius degree and after that decreased. The effect of pressure on the phenolic compounds wasn’t remarkable. The amount of flavonoid compound was between 142.87 and 290.21 mg equivalent catechin per 100 g dry material. The most effective parameter among investigated parameters (temperature, pressure, and ratio), was temperature. The pressure of extraction in subcritical water extractions did not have any significant effect and every change in laboratory results was very smallThe best results were observed at 147 Celsius degrees, pressure 10 bar, and 1:19 ratio. In these optimum conditions, the amount of total phenolic compounds, total flavonoid compounds, stability power, radical scavenging power, and reduction power was 2497.8 mg gallic acid per 100 g dry material, 267.99 mg flavonoid compounds catechin equivalent per 100 g dry material, 7.44 h, 1370.77 ppm, and 362.94 ppm respectively. Reduction and stability power with radical scavenging ability of pistachio hull extracts were very near to BHT as well as a synthetic antioxidant. Results showed that the extracts obtained from pistachio hull by subcritical water had high amount of phenolic compounds and had the same antioxidant properties as the synthetic antioxidant BHT
Food Chemistry
Elham Ranjbar Nedamani; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Charlotte Jacobsen; Vahid Khouri
Abstract
The aim of the present study was to use the Maillard reaction as a means to glycosylate protein hydrolysates obtained from Cajanus cajan and to evaluate the effects of this chemical modification on antioxidant and emulsifying properties. Chemical properties, amino acid composition, and molecular weight ...
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The aim of the present study was to use the Maillard reaction as a means to glycosylate protein hydrolysates obtained from Cajanus cajan and to evaluate the effects of this chemical modification on antioxidant and emulsifying properties. Chemical properties, amino acid composition, and molecular weight distribution of the hydrolysates were evaluated. Glucose, galactose, and maltodextrin in the ratios of 1:2, 1:1, and 2:1 (hydrolysate: sugar, dry weight basis) were used for glycosylation. Antioxidant activity was evaluated by 1, 1- diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and nitric oxide scavenging. The sonication technique was used to prepare the (oil/water) emulsions. The droplet size distribution and zeta potential of the emulsions were measured during 4 days of storage. Results showed that glycosylation by glucose in the ratio of 2:1 increased DPPH scavenging activity from 37.96% to 85.53% and nitric oxide inhibition activity from 14.50% to 54.83%. Although glycosylation improved emulsifying stability of glycosylated hydrolysates compared to non-glycosylated hydrolysates, no significant difference was observed between the three examined sugars.
Food Technology
Fahimeh Hajinia; Alireza Sadeghi; Alireza Sadeghi Mahoonak; Morteza Khomeiri; Yahya Maghsoudlou; Ali Moayedi
Abstract
Introduction: Bread is the main source of nutrients and it is a cheap staple food in the daily diet of people in many parts of the world. One of the most important ways to improve the quality of bread is to ferment cereals and use fruit resources. Cereal fermentation has a well-known potential to improve ...
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Introduction: Bread is the main source of nutrients and it is a cheap staple food in the daily diet of people in many parts of the world. One of the most important ways to improve the quality of bread is to ferment cereals and use fruit resources. Cereal fermentation has a well-known potential to improve the nutritional properties of the baked goods. It stabilizes the levels of various bioactive compounds, retards starch retrogradation and increases mineral bioavailability. A diet rich in cereal and fruit-based products could improve human health. Oat grain has a high functional potential due to its composition. This grain is known to be an excellent source of dietary fiber, antioxidants and a well-balanced protein fraction. Jujube fruit is also getting popularized due to the high content of vitamins, phenolic, polysaccharides and natural colorant agents. The quality of available commercially jujube depends on the contents of its bioactive compounds and micronutrients. There is no report about simultaneous application of fermented oat and jujube powder in processing of wheat bread. Accordingly, the aims of this study were to produce a supplemented wheat bread containing these ingredients, and evaluate the textural and antioxidant properties of the product. Materials and methods: In the present study, controlled fermented oat containing selected LAB isolated from oat sourdough (as starter culture) was used to produce supplemented wheat bread. Crumb hardness, porosity, specific volume, overall acceptability and antioxidant activity in wheat bread containing fermented oat, jujube powder and their mixture were investigated in comparison with the control (wheat bread). All the experiments were done in triplicates. A complete randomized design with the least significance difference (LSD) post-hock was also used to statistical analysis of the data at p < /em>< 0.05 by SPSS (version 20) software. Results and Discussion: The highest amount of crumb hardness was observed in the sample containing mixture of controlled fermented oat and jujube powder, meanwhile the lowest amount of hardness was belonged to the control sample. The results of specific volume showed an inverse relationship between the values of hardness and specific volume, and the lowest specific volume was observed in sample containing controlled fermented oat along with jujube powder. The highest amount of specific volume was also observed in the control sample. The porosity of all the produced breads was also significantly (p < /em><0.05) higher than the control sample, and the highest porosity was observed in the sample containing controlled fermented oat. The amount of produced gaseous compounds and carbon dioxide during fermentation affect the porosity of the produced bread. Furthermore, water retention capacity is also involved in increase in bread specific volume. Water reduces the stiffness of protein structures and allows better air to enter the dough texture and more specific volume of the product. Wheat breads containing controlled fermented oat + jujube powder and jujube powder (alone) had the highest antioxidant activity, and the control sample had the lowest antioxidant activity. During fermentation, the amount of phenolic compounds or flavonoids increases, and fermentation also causes the synthesis or release of various compounds that have antioxidant properties. Characterization of wheat bread containing the optimal formulation of controlled fermented oat and jujube powder didn’t show significant effect on the overall acceptability of the product. The presence of fiber in fortified breads is likely to increase water uptake, which in turn increases water retention capacity, reduces dough stability and increases overall acceptability. Fruits and whole grains are rich in phytochemicals such as phenolic compounds. Application of phenolic compounds in bread processing, in addition to improve antioxidant properties, affects the physicochemical properties of the dough and the quality characteristics of the produced bread due to various interactions with flour compounds such as gluten and starch. Accordingly, the combined use of plant-rich resources such as jujube powder and fermented oat, which are rich in minerals and micronutrients, can be used to improve the nutritional and quality characteristics of the supplemented wheat bread as a simple and efficient method. Due to the adverse effects of chemical additives and improvers, the importance of providing natural alternatives such as fermented substrates and plant resources in wheat bread processing is quite necessary. The best alternatives for this purpose include sourdough and fiber-rich plant. Wheat bread containing a mixture of controlled fermented oat and jujube powder had the highest crumb hardness and the lowest specific volume. Antioxidant activity in all samples was significantly higher than the control sample and wheat bread containing a controlled fermented oat and jujube powder with 90.52% had the highest amount of antioxidant activity. According to the results, controlled fermented oat and jujube powder, as functional ingredients, may be successfully incorporated into the wheat bread with positively effects on its quality characteristics.
Food Technology
Somayeh Ghandehari alavijeh; Mehran Alami; Yahya Maghsoudlou; Alireza Sadeghi Mahoonak
Abstract
Introduction: Porous starch granules are becoming of great interest such as non-toxic absorbents, owing to their great absorption capacity derived from the major specific surface area. Pores can protect sensitive elements as oils, minerals, vitamins, bioactive lipids, food pigments such as beta-carotene ...
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Introduction: Porous starch granules are becoming of great interest such as non-toxic absorbents, owing to their great absorption capacity derived from the major specific surface area. Pores can protect sensitive elements as oils, minerals, vitamins, bioactive lipids, food pigments such as beta-carotene and lycopene that are sensitive to light, oxidation or high temperature. Alpha-amylases from Bacillus and glucoamylases from Aspergillus niger have the strongest hydrolytic ability toward starch. Ultrasonic treatments have been reported to produce modified starch. In the last years, the effects of sonication on the starch microstructures and properties have been studied. It was shown that the C–C bonds of starch granules were destroyed, and hollows or pores were formed on the surface and inside the granules. Therefore, the main objective of this study was to identify a suitable starch (corn or wheat) to carry and protect iron ions. The enzyme having a fixed concentration of 0.1% within a fixed period of 36 hour, was added to the starch solutions in three different steps - after, simultaneously and before - the ultrasound processes. The power of the ultrasound was 350 watt for 10 minutes. Iron ions (Iron Ammonium Sulfate (II)) were added to the porous corn and wheat starches in concentrations of 40, 60 and 80 ppm. Materials and methods: The ability of water and oil adsorptions were measured in the produced corn and wheat porous starches. The microstructures of porous starches were revealed by using Scanning Electron microscopy (SEM). After adding iron ammonium sulfate (II) to the porous starches of corn and wheat, the amount of iron ions absorbed and the type of bonds formed between starch and iron ions were determined by inductively coupled plasma (ICP) and infrared spectroscopy (FTIR), respectively. Statistical analysis was performed by using SPSS software and the mean comparison test at 5% probability level and in the form of factorial test. Results & Discussion: The hydration capacity in processed wheat starch was lower than corn starch due to the differences in granular structure of wheat and corn starch. The hydration capacity in native wheat and corn starches was significantly (p < 0.05) lower than the processed forms. No significant difference (P>0.05) was observed between the three steps of adding enzyme (e after, simultaneously and before the ultrasound processes). According to the results, the oil adsorption capacity in the processed starches was more than that of the native forms. Scanning Electron Microscopy (SEM) shows that the native corn and wheat starch granules appeared without any clear of fissures, fractures and pores. The corn and wheat starches which were treated by the enzyme after (step 1), simultaneously (step 2) and before (step 3) the ultrasound change and lose their smooth surfaces and become uneven. The surface of corn granules in group 2 and 3 have less pores and porosities with more laminated. In simultaneously processes (phase 2) the ultrasound causes the enzyme to be inactivated. In phase 1, it can be concluded that the ultrasound helps the enzyme performance in creating the porosities and cavities. The wheat granules in step 1, 2 and 3 have a lot of damage on the surface and it is likely that the surface of the wheat granule is more resistant to enzyme penetration than the corn. The results of the ICP test show that processed corn starch has significantly (P <0.05) greater ability to absorb iron ions than processed wheat starch. Also, corn starch had a significant difference in iron uptake in the step 1 than steps 2 and 3 (P <0.05), but the data of the second and third steps did not differ significantly (P> 0.05). Hydroxyl groups of D-glucose units in starch granules bond with iron ions and FTIR spectrums give drop at 575 (cm-1) wavelengths. This study showed that enzymatic treatment and ultrasound led to the native corn starches convert to porous starches. The corn starch is more suitable than the wheat because the wheat is more resistant and the cavities were rarely formed. The corn porous starch is a suitable carrier for iron ions.
Elham Ranjbar Nedamani; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Sharlot Jakobson; Vahid Khori
Abstract
Introduction: Proteins are being hydrolyzed to generate various properties such as antioxidant activity and nutritional values. Enzymatic hydrolysis is carried out in milder condition and is more controllable. The produced protein hydrolysates’ properties are dependent to the hydrolysis condition. ...
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Introduction: Proteins are being hydrolyzed to generate various properties such as antioxidant activity and nutritional values. Enzymatic hydrolysis is carried out in milder condition and is more controllable. The produced protein hydrolysates’ properties are dependent to the hydrolysis condition. So by optimizing the hydrolysis conditions, proteins with higher antioxidant abilities are achieved. Response surface method is a statistical way to optimize and model the process more efficiently. The aim of present study was to optimize and model the hydrolysis condition to produce and antioxidant protein hydrolysate with high nutritional value from Cajanus cajan by pepsin. Materials and methods: First, Cajanus cajan’s proteins solubility was measured. After reaching the pHs with the most and least solubility, protein extraction was carries out by using NaOH and HCl. Enzyme concentration (1, 2, 3%), temperature (30, 35, 40 °C) and time (2, 3.5, 5 h) as independent variables were given to the Design Expert software and protein hydrolysis was done in a shaker incubator according to the 20 treatments suggested by the software. 1, 1- diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity, hydroxyl radical scavenging activity, Reducing power and total antioxidant activity were measured as dependent variables. Antioxidant assays were modeled by the software and the optimum condition was evaluated. The obtained optimum condition was validated by repeating the antioxidant assays for the protein hydrolysate produced in the optimum condition. The amino acid profile of the protein hydrolysate was measured using HPLC-MS and chemical score was measures. Then, the molecular weight distribution of the protein concentrate and protein hydrolysate was evaluated by FPLC. Chemical composition of the samples was also measured. Results & discussion: The optimum condition for achieving antioxidant protein hydrolysate was enzyme concentration 2.15%, temperature 39.99 °C and time 4.52 h. Model validation results for this point were including DPPH scavenging activity 58.49%, reducing power 0.31 nm, hydroxyl radical scavenging activity 38.2% and total antioxidant capacity 0.63 nm. The protein concentrate consisted of 215.84 mg/g hydrophobic and 57.04 mg/g of them were aromatic amino acids. These amino acids are responsible for antioxidant activity of the protein hydrolysates. Chemical scores for essential amino acids were good. Most of the peptides in the protein hydrolysate had molecular weights below 10 kD that is considered to have antioxidant activities. Hydrolysis also increased the protein and ash content while fat and water content decreased compared to the Cajanus cajan’s flour and protein concentrate. Results showed that Cajanus cajan’s protein hydrolysate can be a good source of antioxidants and play a positive role in human nutrition.
Najimeh Taghavi; Aman Mohammad Ziaiifar; Habibollah Mirzaee; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Hassan Sabbaghi
Abstract
Introduction: Frying is a unit operation in which food is heated in oil to alter its eating quality. First reviews of frying performed on the principles of heat and mass transfer and oil uptake in foods, because during the frying process heat and mass transfer occurred between product and frying medium. ...
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Introduction: Frying is a unit operation in which food is heated in oil to alter its eating quality. First reviews of frying performed on the principles of heat and mass transfer and oil uptake in foods, because during the frying process heat and mass transfer occurred between product and frying medium. In fact, the food loses moisture content and lost water will replace with oil. The moisture loss in the product causes rapid formation of the crust while the core remains soft and moist; therefore higher oil uptake occurred in the crust. There is an argument about the effect of frying on the sensory characteristics of foods, changes of nutritional value and health concerns in fried foods and methods applied to reduce oil content. Consumers prefer eating foods with lower oil content. One of the typical methods for reducing oil uptake in food commodities is using of coating before frying process. Edible coatings are known as a thin layer of edible polymers which is placed on the surface of the food. Application of edible coating decreases some destructive factors like the presence of various gases such as oxygen and carbon dioxide and humidity. Hydrocolloides are referred to a group of polysaccharides and proteins which create many features such as consistency in aqueous solutions, foams stability, emulsions, improve the sense of mouth and create a similar state of fatty and oily mode for products with lower content. In fact hydrocolloid coatings can reduce the excessive oil uptake due to their interesting thermogelling properties and at the same time they are invisible and have no negative influence on the sensory attributes of fried foodstuff. Even more, fried products have low fat content with improved nutritional values, higher crispiness and better palatability. Pishmeh is described as deep-fried dough pastry which is usually prepared by local producers of Turkmen (Iran). This product absorbed high oil content during frying process. This study was carried out to evaluate the effects of hydrocolloid coatings including Aloe Vera, Carboxymethyl cellulose (CMC) and Xanthan on the oil uptake of Pishmeh.
Materials and methods: Hydrocholloid materials such as Aloe Vera, Carboxymethyl cellulose (CMC), Xanthan and complex of Xanthan-CMC were used. The gums were prepared at concentrations of 0.5 and 1% by dissolving in water at 70 ° C by stirring with a homogeneous mixer until a clear suspension was obtained. To extract the Aloe Vera gel, first, a thick epidermis (The shell) was separated from parenchyma using cutter. The parenchyma was immersed in a container of distilled water to lose bitter taste for 5 minand then parenchyma was taken out from water and transferred into a mixer (for 1 minute at 25 °C) and finally converted to a uniform colloidal solution. In the next step, the prepared dough samples were immersed in the colloidal suspensions for 1 min and the coated samples were placed on a mesh tray to remove the excess residuary coats. The samples were fried in sunflower oil at 170 °C for 6 min. The samples were then placed on a metal tray after frying to remove excess oil. After removing the oil and reaching the ambient temperature, physical and chemical tests were carried out on the sweet Pishmeh. The experiments included determination of moisture, fat content, measurement of coating parameters (such as coating ratio and frying efficiency) and color analysis.
Results and Discussion: The result showed that coating by hydrocholloid materials was led to decrease water loss in comparison to non-coated sample (control) during frying. Furthermore, oil uptake of coated samples was lower than control sample (p
Atefe Maqsoudlou; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Fidel Toldta
Abstract
Introduction: Bee pollen, commonly referred as the ‘‘life-giving dust’’, results from the agglutination of flower pollens with nectar using salivary substances of the honeybees (Almeida-Muradian et al., 2005). Pollen contains 10 to 40% protein, 1 to 13% lipid, 13 to 55% carbohydrates and 2 to ...
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Introduction: Bee pollen, commonly referred as the ‘‘life-giving dust’’, results from the agglutination of flower pollens with nectar using salivary substances of the honeybees (Almeida-Muradian et al., 2005). Pollen contains 10 to 40% protein, 1 to 13% lipid, 13 to 55% carbohydrates and 2 to 6% minerals. Royal Jelly is produced by enzymatic digesting of bee pollen by proteases and other natural enzymes. Based on dry weight, it contains 27-41% protein, 30% carbohydrates, 8-19% lipids, minerals, trace elements and some vitamins (Sabatini et al., 2009; Wytrychowski et al., 2013). The antioxidant properties of royal jelly and bee pollen, are related to main proteins and phenolic compounds and flavonoids (Nagai and Inue, 2004). The antioxidant activity of peptides can be evaluated using DPPH, radicals scavenging activity, Ferric reducing, Ferrous chelating activity (Khantaphant et al., 2011). Antioxidant and ACE inhibitory activity of pollen, royal jelly and peptides were investigated by different researchers (Bogdanov, 2014; Morais et al., 2011; Salampessy et al., 2015; Marinova and Tchorbanov, 2010; Wiriyaphan et al., 2012). The objective of present research was optimization of enzymatic hydrolysis of bee pollen protein by Alcalase according to its antioxidant and ACE inhibitory activity compared to royal jelly.
Materials and methods: The preparation of the bee pollen extract was performed by mixing the bee pollen with water (1:10) (w/v). The macerates were filtered and centrifuged at 12000 g. The obtained supernatant was lyophilized. The royal jelly extract were prepared using method described by Liu et al., 2008. The total phenolic content of the extracts was recorded using the Folin–Ciocalteu method (Moreira et al., 2008). DPPH radical-scavenging activity was determined as described by Bersuder, Hole, and Smith (1998). The ability of the hydrolysate to reduce iron (III) was determined according to the method of Bougatef et al. (2008). Bee pollen was added and homogenized with 5 volumes of distilled water. pH and temperature of the solution were adjusted to pH=8 and 50◦C. Alcalase in the concentration range of 1 to 2% w/w were added to the pollen protein solution. Enzymatic hydrolysis performed during different times 2 to 5 hours. Hydrolysis was stopped by heating at 80˚C for 10 min. The hydrolysats were centrifuged at 4000x g for 30 min to remove the residue. The supernatants were pooled and then lyophilized (Matsuoka et al., 2012). DPPH radical scavenging ability and reducing power of pollen hydrolysates of pollen hydrolysates were measured. Also ACE-inhibitory activity of pollen hydrolysates was measured was assayed by method reported by Nakamura et al. (1995). Statistical analysis of results before hydrolysis was done by SPSS. Optimization of enzymatic hydrolysis was done by Response Surface Methodology (RSM) in Design Expert software.
Results and discussion: Total phenol value measured for pollen ranged between 48.15 to 174 mg Gallic acid/g for royal jelly ranged from 9.24 to 87.261 mg Gallic acid/g. Considering that royal jelly is obtained by direct digestion of pollen, the amounts of their phenolic compounds were comparable (Bogdanov, 2014). Phenolic compounds increased by increasing concentration royal jelly and pollen extract in dose dependent manner. Increasing concentrations of royal jelly in range of 300 to 1000 mg/l was more effective than pollen (p
Adel Dezyani; Aman Mohammad Ziaiifar; Seyed Mahdi Jafari; Mohammad Ghorbani; Alireza Sadeghi Mahoonak
Abstract
Introduction: High sensitivity of fruit and vegetables juices to heat has been resulted to the development of spray drying method for drying this category of products. Spray drying is a well-established and widely used method for transforming a wide range of liquid food products into powder form. The ...
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Introduction: High sensitivity of fruit and vegetables juices to heat has been resulted to the development of spray drying method for drying this category of products. Spray drying is a well-established and widely used method for transforming a wide range of liquid food products into powder form. The process involves spraying finely atomized solutions into a chamber where hot dry air rapidly evaporates the solution leaving the spray-dried particles. Spray-dried powders can be stored at room temperature for prolonged periods without compromising the powder's stability. Powders are cheaper to transport and easier to handle in manufacturing plants. Spray-dried powders are economical to produce compared to other processes, such as freeze-drying. Spray drying has many applications, particularly in the food, pharmaceutical and agrochemical industries. The conversion of high value food materials, such as fruit and vegetable extracts, into particulate form is not easy due to the presence of a high proportion of low molecular weight sugars in their composition which lead to the problem of stickiness. The particles stick to one another, to the dryer and to cyclone walls and remain there, forming thick wall deposits, while very little product comes out at the dryer's exit. This might lead to low product yield and operating problems. In general, the stickiness causes considerable economic loss and limits the application of spray drying on foods as well as on pharmaceutical materials. In order to reduce stickiness, different solutes have been used as carriers and coating agents for the spray drying. Some examples of these are Arabic gum, maltodextrins, starches, gelatin, methyl cellulose, gum tragacanth, alginates, pectin, silicon dioxide, tricalcium phosphate, glycerol monostearate and mixtures of some of them. Of these additives, maltodextrin offers a good compromise between cost and effectiveness. It has been found that it contributes to the retention of some food properties, such as nutrients, color and flavor, during spray drying and storage. On the other hand, the feed flow rate, the inlet and outlet air temperatures, atomizer speed, feed concentration, feed temperature and inlet air flow rate are important factors that have to be controlled in a spray drying process. Tomato paste is a typical example of a product that is very difficult to be spray dried due to the low glass transition temperature of the low molecular weight sugars present.
Materials and methods: This study was carried out to evaluate the effect of inlet air temperature of dryer (120, 150 and 180 °C) and concentration of drying aid or carrier agent of maltodexterin along with whey protein concenterate ratio of 4 to 1 (25, 37.5 and 50% w/w) on the quantitative and qualitative properties of tomato paste powder including moisture content, bulk density, solubility, powder morphology, amount of lycopene, and production efficiency. Response surface methodology was used to choose optimum conditions of the powder production process.
Results and Discussion:the results revealed that the production efficiency (not significant) and solubility (significant) were increased with increased higher inlet air temperatures of dryer; however, at these conditions moisture content (significant), bulk density (not significant) and amount of lycopene (significant) in the powder were decreased also higher concentrations of carrier agent increased the production efficiency, solubility and amount of lycopene in the powder; however, moisture content and bulk density of powder were decreased.
Conclusion: Optimal conditions in order to achieve maximum production efficiency, solubility, the amount of lycopene and the lowest moisture content of powder, bulk density were achieved at inlet temperature of 150°C and carrier agent concentration of (w/w) 50%.
Elham Nourmohammadi; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Mehran Alami; Masoumeh Sadeghi
Abstract
Introduction: Proteins are vital substances for health since they provide nitrogen, amino acids and the energy required for normal body performance. However, the applications of proteins are limited due to their certain properties, such as their low solubility. The enzymatic hydrolysis of proteins is ...
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Introduction: Proteins are vital substances for health since they provide nitrogen, amino acids and the energy required for normal body performance. However, the applications of proteins are limited due to their certain properties, such as their low solubility. The enzymatic hydrolysis of proteins is an extensively used approach to produce bioactive peptides and promote the chemical, functional and nutritional properties of proteins. These compounds have interesting biological properties such as anti-oxidative, anti-hypertensive, anti-bacterial, anti-cancer and anti-thrombotic activities. Lipid peroxidation is one of the main reasons behind the deterioration of foodstuffs during processing and storage. In this case, the addition of anti-oxidative compounds is considered as an effective way to improve the shelf-life of lipid containing foods. Due to carcinogenic effect of synthetic anti-oxidative compounds, extensive efforts have been done to find natural anti-oxidative compounds with plant origin during recent years. Pumpkin (Cucurbitapepo) seeds are rich of proteins, unsaturated fatty acids, phytosterols and essential minerals like Zn, K, Ca, Mg, Fe, Cu and P. Oil content of pumpkin seeds is about 40-60%, and mostly consisted of oleic, palmitic and stearic acids. On the other hand, its protein content is about 45-46%, and this amount will reach to 55-56% after defatting. To date, pumpkin seeds have been mainly used for pumpkin oil production. After the oil extraction, a protein-rich by-product (pumpkin oil cake) remains, which is often used for animal feeding. In this study, the enzymatic hydrolysis of pumpkin oil cake protein isolate by a food-grade protease named trypsin was attempted and the optimum treatment was selected based on the DPPH radical scavenging and ferrous ion chelating activities Materials and Methods: In this study, the optimization of the hydrolysis of pumpkin (Cucurbitapepo) oil cake protein was investigated using response surface methodology (RSM) and central composite design (CCD) in order to achieve the maximum DPPH radicals scavenging and metal ion chelating activities. For this purpose, trypsin concentrations of 1-2% and hydrolysis temperatures and times of 35-45 ċ and 2-5 hours were examinedas independent variables. Preparations of pumpkin oil cake protein isolate (POCPI) Defatted pumpkin oil cake was dispersed in distilled water (1:10 w/v). The pH was adjusted to 10 with 1N NaOH, mixed for 1 hour at room temperature and centrifuged at 5000g for 20 minutes (Combi514R, South Korea). The supernatant was collected, pH was adjusted to 5 with 1N HCl and centrifugation was performed at the same condition. Supernatant was discarded and precipitate was collected as pumpkin oil cake protein isolate. Enzymatic hydrolysis Pumpkin oil cake protein isolate was dispersed in tris-HCl at pH= 8 for trypsin enzymatic treatment (5% w/v). After that, trypsin was added at 1%, 1.5% and 2% and hydrolysis was carried out for 2, 3.5 and 5h at 200 rpm in shaker incubator (8480-VS, South Korea). Hydrolysis temperatures were 35, 40 and 45˚C. At the end of hydrolysis, the enzyme was inactivated for 15 minutes at 85˚C; dispersion was centrifuged at 4000g for 30 minutes, the supernatant was collected and freeze dried. DPPH radical scavenging activity An aliquot of 1000 microliterpumpkin oil cake proteinhydrolysate was mixed with 1000 microliter of 0.1mM DPPH solution prepared in 96% ethanol. The mixture was allowed to stand for 60 minutes in the dark and the absorbance was read at 517 nm. The blank was prepared with the same manner except that 1000 microliter water was used instead of 1000 microliter pumpkin oil cake proteinhydrolysate. Ferrous ion chelating activity Pumpkin oil cake protein hydrolysate(4.7 ml) was mixed with 0.1 ml 2mM FeCl2 and 0.2 ml 5 mM ferrozine and was kept at room temperature for 20 min. The absorbance was read at 562 nm and the blank sample was prepared with the same manner except that 4.7 ml distilled water was used instead of sample. Results & Discussions: The results of this study, showed that the optimum conditions to reach the maximum DPPH radicals scavenging and metal ion chelating activities were 35 ċ, 5h, 1.1% enzyme concentration and 45 ċ, 2.05h and 2% enzyme concentration that showed DPPH radicals scavenging and metal ion chelating activities of 76.28% and 49.61% respectively. These results were to large extent similar to those suggested by Design Expert software (75.89% and 50.84%). The R2 was 0.9184% and 0.9761% for DPPH radicals scavenging and metal ion chelating activities respectively. Moreover the adjusted R2 was estimated to be 0.1333 and 0.1827 for DPPH radicals scavenging and metal ion chelating activities respectively, which suggested the suitability and fitness of proposed model for the considered responses. Conclusions: Based on the results, pumpkin oil cake protein hydrolysate demonstrated appropriate anti-oxidative and metal ion chelating abilities. The results of this study indicated that pumpkin oil cake protein hydrolysate had the ability to be used as an effective and natural anti-oxidative compound in lipid containing foods.
Mohammadmahdi Seyedabadi; Mahdi Kashani-Nejad; Alireza Sadeghi Mahoonak; Yahya Maghsoudlou; Fakhreddin Salehi
Abstract
The turbidity of sour orange juice after juice extraction affects on quality, shelf-life and concentration of juice. Therefore, juice clarification is an important operation in the fruit processing industry. The goal of this study was evaluating the effect of membrane operation parameters including pressure ...
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The turbidity of sour orange juice after juice extraction affects on quality, shelf-life and concentration of juice. Therefore, juice clarification is an important operation in the fruit processing industry. The goal of this study was evaluating the effect of membrane operation parameters including pressure (120-220 kPa) and temperature (25-35 ºC) on the permeate flux and hydraulic resistance of sour orange juice during membrane clarification. Response surface methodology (RSM) was used to optimizing the operating parameters. Results of the experiments showed that the permeate flux was raised with increasing of temperature, but total hydraulic resistance (RT), concentration polarization resistance (Rcp) and gel layer resistance (Rg) was decreased in mentioned condition. The permeate flux, membrane resistance (Rm), RT, Rcp and fouling index was raised with increasing in pressure. The Rm and fouling index are showed different behavior depending on temperatures level. Results of process optimization indicated that the best conditions to maximize of permeate flux, and to minimize of fouling index and RT achieved at 35 ºC and 120 kPa for a maximum desirability of 0.761.
Seyed Yousef Pourmir; Alireza Sadeghi Mahoonak; Javad Fattahi Moghadam; Yahya Maghsoudlou; Mohammad Ghorbani
Abstract
Introduction: Citrus fruits, which belong to the family of rutaceae are one of the main fruit tree crops grown throughout the world. Although sweet orange (Citrus sinensis) is the major fruit in this group accounting for about 70% of citrus output.Citrus fruits are well – appreciated fortheir refreshing ...
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Introduction: Citrus fruits, which belong to the family of rutaceae are one of the main fruit tree crops grown throughout the world. Although sweet orange (Citrus sinensis) is the major fruit in this group accounting for about 70% of citrus output.Citrus fruits are well – appreciated fortheir refreshing juice and health benefits.The health benefits of citrus fruits are linked to the high amounts of photochemical and bioactive compoundssuch as flavonoids, carotenoids, vitamins and minerals available in their juice.These phytonutrientsmay act as antioxidants, stimulate the immune systems; induce protective enzymes in theliver or blockthe damage of the genetic materials. The phytonutrients and vitamins may be responsible for theantioxidant, anticancer and anti-inflammatory properties of the citrus species.Citrus fruits processing accounts for approximately one third of total citrus fruitproduction, more than 80% of it is orange processing, mostly for orange juice production.The most important processed citrus fruits product isorange juice. Orange juice can be presented in different forms. The major types of orangejuice are the freshly squeezed orange juice and concentrated orange juice.Siavaraz local orange is an orange cultivar grown in north of Iran which is used mainly in orange juice production. There is no systematic study about the relation between physical characteristic of fruit at harvest time and its juice quality and quantity. Materials and methods:In this study, the physical characteristics, quantitative-qualitive properties of siavaraz local orange at harvesting times and changes in anti-oxidant components of its juice during processing and storage were investigated.The fruit were collected in eleven different harvest time (start of fruit harvesting and every two week intervals) and different parameters including fruit length, diameter, spherical coefficient, density, peel thickness, juice percentage, total soluble solid (TSS),titrable acidity(TA) were evaluated. In next stage ascorbic acid, total phenolics and anti-oxidant capacity of different fruit juice include fresh squeezed juice by hand and extractor, juice reconstituted from orange concentrate with 60° brix, juice reconstituted from orange concentrate with 65° brixwere evaluated and compared. Finally, changes in vitamin C content during refrigerated storage infresh squeezed juice by hand andjuice reconstituted from orange concentrate were measured. Results & Discussion:Results showed that siavaraz local orange was in four size with different physical characteristics. The highest amount of density was belonged to small fruits with 0.977 at the first harvest stage. Small oranges with lowest peel thickness had the highest juice percentage but the large oranges with the higher TSS showedhigher production efficiency (327.24%). The TA and pH in first stage of harvest were the highest and the lowest, respectively compared to other stage. The highest concentrate efficiency (6.42%) and juice quality (9.88° brix) were obtained at the harvest stagenumber six and seven, respectively. The lowest amount of juice percentage for concentrate production was observed at the stagenumber six (15.6 kg). By investigating the anti-oxidant compounds, results reveals that ascorbic acid and anti-oxidant capacity of juice taken by juicer extractor, were higher (p
Mahdi Kashani-Nejad; Alireza Sadeghi Mahoonak; Seyed Mohammad Ali Razavi
Abstract
Introduction: Honey is a natural food product having a high nutritional and medicinal value. It is a sweet, viscous substance produced by the honeybees from the nectar of plants. Sensory and physical properties and chemical composition of honey depend on the botanical origin and the regional and climatic ...
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Introduction: Honey is a natural food product having a high nutritional and medicinal value. It is a sweet, viscous substance produced by the honeybees from the nectar of plants. Sensory and physical properties and chemical composition of honey depend on the botanical origin and the regional and climatic conditions of the area in which it is produced.The knowledge of honey rheology is very important for its processing, quality control, process control, and selection of proper process equipment, storage, handling, and transportation and plays an important role in fluid heat transfer. Rheological properties of honeys depend on many factors including composition, temperature, and amount and size of crystals. Different kinds of honeys with various floral origins (such as Rosa, Thyme, Astragalus, Trifolium, sunflower, Medicago, alfalfa and etc.) are produced in different regions of Iran. In this study, some physicochemical and rheological properties of four Iranian honeys from Golestanprovienceobtained from various floral sources, two poly floral (Mountain, Forest) and two mono floral (Sunflower, Ivy) were compared with adulteratedand sugar honeys.Materials and methods: Sixhoney samples were collected directly from beekeepers in Golestan Province,two monofloral (Sunflower, Ivy) and two polyfloral(Mountain, Forest), adulterated and sugar honeys. Some physico–chemical characteristics of samples including water content, Hydroxymethylfurfural content (HMF), diastase activity, pH, ash, free acidity, reducing sugars (fructose and glucose), sucrose contentand electrical conductivity were determined by the harmonized methods of the International Honey Commission. The rheological measurements were also carried out on the honey samples at eighteen rotations, ranging from 5-200 rpm and at five temperatures, ranging from 10-30ºC, using a viscosimeter Brookfield.Results and discussion: The samples were found to be different from each other in terms of physico-chemical properties. In the natural honey samples, this discrepancy can be due to diversity in original plant and harvesting season. All the values obtained in the natural honey samples were agreement with those reported by Codex Alimentarius and ISIRI. The values of sucrose and fructose/glucose ratio the sugar honey sample and sucrose, fructose/glucose ratio, pH, HMF, diastase activity of adulterated honey were not in the range suggested by Codex Alimentarius and ISIRI. Conclusion: Rheological characteristics of honeys were evaluated at different temperatures (10, 15, 20, 25 and 30ºC). All the honeys exhibited Newtonian behavior for shear rate in range of 1.045- 41.8 s-1.The temperature dependence of viscosity was described using the Arrhenius and the Vogel–Taumman–Fulcher (VTF) equations.Two models (Power Law and Exponential models) were also investigated to describe the concentration (ºBrix) dependence of viscosity
Hassan Sabbaghi; Aman Mohammad Ziaiifar; Alireza Sadeghi Mahoonak; Mahdi Kashani-Nejad; Habibollah Mirzaee
Abstract
Introduction: Heat transfer processes are important for almost all aspects of food preparation and play a key role in determining food safety. Temperature difference between the source of heat and the receiver of heat is the driving force in heat transfer. Convection is the transfer of heat by the movement ...
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Introduction: Heat transfer processes are important for almost all aspects of food preparation and play a key role in determining food safety. Temperature difference between the source of heat and the receiver of heat is the driving force in heat transfer. Convection is the transfer of heat by the movement of groups of molecules in a fluid. The groups of molecules may be moved by either density changes or forced motion of the fluid. In a typical convective heat transfer a hot surface heats the surrounding fluid, which is then carried away by fluid movement. The convection heat transfer coefficient or h value is defined as the rate of heat that will be convected at the product surface–fluid interaction through a unit surface area of the material if a unit temperature gradient exists between the product surface and the surrounding fluid and is very important in modeling and design of frying systems for foods. Frying is a very turbulent process with random and dynamic movement of small bubble particles over the boundary layer of the product surface. Deep fat frying is a very fast method of food processing among conventional heat transfer methods. The frying by immersion can be divided into four stages: (1) initial heating (the temperature of the internal part is slowly increased to boiling point); (2) surfaces boiling (crust formation and higher oil turbulence); (3) falling rate (long period, vapor transfer at the surface decreases) and (4) bubble end point (dried product). These four states during frying can be generalized as non-boiling phases (stages 1 and 4) and boiling phases (stages 2 and 3). So, Convection heat transfer during immersion frying may be divided into two stages: 1) free convection during initial heating of the material and 2) forced convection during the boiling phase. In this study, the convective heat transfer coefficient investigated as a function of the water loss rate during frying process due to the effects of evaporation and boiling on this thermal parameter. Understanding of changes in heat transfer coefficient for thermal control of the frying process is very important to achieve optimum quality of product. Materials and Methods: The potato stripes with specified size are fried at temperature of 145, 160 and 175 °C for 60, 120, 180 and 240 seconds using sunflower oil. The center and surface temperatures of potato stripes were recorded with two-second intervals using T type thermocouple and data logger. Moisture content of French fries was measured by drying them within an oven instrument. Mean moisture and oil content of potato stripes was measured. The h value was estimated and its changes studied during process using heat energy balance between the sample and oil by assuming that total heat transferred by convection from oil to potato is equal to the sum of energy spent on heating potato and energy spent on water evaporation. Moreover, changes in the fraction of total heat used for evaporation at different temperatures were expressed as an empirical model. Results and Discussion: The results showed that the temperature at the center increased up to the evaporation temperature (“A” zone: about 60 seconds after process beginning). Then, it remained constant at this temperature for a while due to evaporation (“B” zone: about from 60 s till 160 s). This constant temperature period decreased as temperature increased. After this period, the center temperature approached to that of oil (“C” zone: increasing product surface temperature to oil temperature). These various stages of the process were separated. The moisture loss rate was high at the beginning of frying and oil uptake increased as the moisture content diminished. As oil temperature increases, the sample moisture content for the same frying period decreases since an increase in temperature results in a higher kinetic energy for water molecules leading to a more rapid moisture loss in form of vapor. The heat transfer coefficient is increased as the oil temperature increased and at the first time of process observed higher h value. It was due to more water loss rate and so the higher turbulence within the oil before crust formation and for elevated temperatures. The maximum heat transfer coefficient for the temperatures of 175, 160 and 145 °C is estimated 943.68, 847.81 and 682.64 W/m2°C, respectively. Estimated h value also shows a linear increase with water loss rate. Since most of the energy used is associated with the evaporation of water present in the potato, for lower temperatures, the fraction of total heat needed to complete the evaporation is higher and it also represents lower h values by reducing the oil temperature. Also, the variation in the fraction of total heat used for water evaporation showed exponential rise to maximum behavior. Conclusion: The proposed model for studying evaporation heat fraction fitted experimental data properly, with standard error values range of 0.01-0.03. Evaporation heat fraction could have been affected by oil temperature changes, water loss rate and h value (linear depend with the water loss rate) during process.
Hamed Hosseini; Mohammad Ghorbani; Alireza Sadeghi Mahoonak; Yahya Maghsoudlou
Abstract
An accelerated shelf-life test using elevated temperatures 62, 72 and 82 ˚C was conducted to predict the oxidation progression of walnuts over a long-term storage. Oxidation parameters including values of conjugated dienes (CD) and trienes (CT) values and thiobarbituric acid (TBA) value were employed ...
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An accelerated shelf-life test using elevated temperatures 62, 72 and 82 ˚C was conducted to predict the oxidation progression of walnuts over a long-term storage. Oxidation parameters including values of conjugated dienes (CD) and trienes (CT) values and thiobarbituric acid (TBA) value were employed to evaluate the oxidation processes. Changes followed an apparent first-order kinetic. Walnuts and walnut kernels were also kept in normal condition (20-30˚С; RH, 35-45%) for 12 months in order to validate the approach. A maximum of energy (62.24-75.67 kJ mol-1 K-1) needed for formation of primary oxidation products and a minimum of energy (35.65 kJ mol-1 K-1) to generate secondary oxidation products were calculated. Formation of oxidation products in walnut kernels was found to be a temperature-dependent reaction, with Q10 =1.44- 2.1. The results showed that CD and CT values could provide a proper estimation for oxidative stability of the nuts stored in ordinary condition, with an average error of approximately 12.9%.
Elham Ranjbar Nedamani; Alireza Sadeghi Mahoonak; Mohammad Ghorbani; Mahdi Kashani-Nejad
Abstract
The aim of present study was to investigate and compare antioxidant properties of green tea and rosemary extracts and determine the effect of their combination on the antioxidant properties. Results of total phenols, DPPH free radical scavenging assay, total antioxidant capacity, reducing power and their ...
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The aim of present study was to investigate and compare antioxidant properties of green tea and rosemary extracts and determine the effect of their combination on the antioxidant properties. Results of total phenols, DPPH free radical scavenging assay, total antioxidant capacity, reducing power and their addition into soybean oil, showed that the green tea extract was significantly (p<0.05) more effective than rosemary, and both of these extracts showed better antioxidant activity than BHT. Combined extracts showed different behavior; in DPPH free radical scavenging assay and reducing power, a significant (p<0.05) synergistic effect was observed, while in total antioxidant capacity and soybean oil the interaction was antagonism, although even in antagonism interaction, these combinations did better than BHT. Consequently, these natural antioxidant combinations can be used as an appropriate alternative for BHT, and that means, lower doses of natural antioxidants results in better protective effect compared to a synthetic ones.
Vida Mardani Ghahfarokhi; Mehran Alami; Saeedeh Arabshahi- Delouee; Alireza Sadeghi Mahoonak
Abstract
In this study, phenolic compounds of evening primrose leaves (Oenothera biennis) were extracted with aceton 70%, ethanol 70% and methanol 70%. Total phenolic content of aceton extract was significantly higher than the ethanolic and methanolic extracts. Extracts were tested for their antimicrobial activity ...
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In this study, phenolic compounds of evening primrose leaves (Oenothera biennis) were extracted with aceton 70%, ethanol 70% and methanol 70%. Total phenolic content of aceton extract was significantly higher than the ethanolic and methanolic extracts. Extracts were tested for their antimicrobial activity against Lactobacillis plantarum and Saccharomyces cerevisiae, using micro broth dilution method. All extracts showed good antimicrobial activity against tested microorganisms. Aceton extract had the most efficient antimicrobial activity. Lactobacillis plantarum was found to be more sensitive to aceton extract than Saccharomyces cerevisiae. The MBC values of aceton extract for Lactobacillis plantarum and Saccharomyces cerevisiae was 0.5 and 1 (μg/ml), respectively. The antimicrobial activity of aceton extract (0.25, 0.5 and 1 μg/ml) was also evaluated in apple juice inoculated using Lactobacillis plantarum and Saccharomyces cerevisiae during 35 days storage at ambinent temprature. Concerning microbial data in apple juice, the extract was able to control Lactobacillis plantarum and Saccharomyces cerevisiae growth. Aceton extract also showed higher inactivation effect on Lactobacillis plantarum in apple juice. Phenolic compounds did not change during 35 days of storage. No change in organoleptic quality of apple juice treated with aceton extract (0.25 μg/ml) was observed, according to sensory evaluation.
Hamed Hosseini; Mohammad Ghorbani; Alireza Sadeghi Mahoonak; Yahya Maghsoudlou
Abstract
Oxidative stability of walnut (Juglansregia L.) was evaluated over a period of 1 year storage in various conditions. The whole walnuts, walnut kernels, walnut chopped kernels, walnut kernels packaged in polyethylene (PET) under vacuum and poly propylene (PP) contain of CO2 were kept in a normal condition ...
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Oxidative stability of walnut (Juglansregia L.) was evaluated over a period of 1 year storage in various conditions. The whole walnuts, walnut kernels, walnut chopped kernels, walnut kernels packaged in polyethylene (PET) under vacuum and poly propylene (PP) contain of CO2 were kept in a normal condition (temperature, 19-30˚С and relative humidity (RH), 35-45%). The whole walnuts and walnut kernels were also kept in refrigerator (4˚С, RH 75%). Some quality parameters for the oil extracted from walnut kernels were measured throughout the storage. Peroxide value of whole walnuts, walnut kernels and walnut chopped kernels pass over 2 meq O2/kg after 12, 10 and 8 months storage, respectively. Peroxide value of the packaged nuts and the nuts stored at cold storage were increased only 1 meq O2/kg over a period of 1 year storage. According to the statistically analysis results, the effect of storage condition and storage time on oxidative stability of walnuts were significant (p walnuts shell > contact surface of walnut kernels with environment were defined to maintain the quality of walnut kernels during long term storage.
Adeleh Soleimani; Mohammad Javad Varidi; Alireza Sadeghi Mahoonak; Mehdi Nasiri mahalati
Abstract
This study was carried out to evaluate the chemical compoition of Alosa Caspia and results compared with Clupeonella engrauliformis which is a common fish catch among Clupeonella and Clupeidae spp in Caspian sea . Results showed that the amount of fat, protein, ash and dry matter in Alosa was higher ...
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This study was carried out to evaluate the chemical compoition of Alosa Caspia and results compared with Clupeonella engrauliformis which is a common fish catch among Clupeonella and Clupeidae spp in Caspian sea . Results showed that the amount of fat, protein, ash and dry matter in Alosa was higher than Clupeonella. The fatty acid composition showed that the EPA was very high in Alosa that show this fish is rich source of omega-3 fatty acid. Then the effect of salting method on moisture and salt content Alosa Caspia were evaluated. The salting methods including traditional (common in north reigon), brining with two salt concentration (saturated and 20% w/w brine) followed by two drying methods (sun and oven drying at 30°) were used. The texture changes during salting showed that salt absorption and water loss was different in different salting method and was higher in traditional salting method. These samples had the lowest moisture at the end of salting, but showed the highest moisture at the end of drying.
Zohreh Karami; Habibollah Mirzaee; Zahra Emam-Djomeh; Alireza Sadeghi Mahoonak; Morteza Khomeiri
Abstract
In this research, anti-microbial activity of ethanolic extract of licorice root against food spoilage microorganisms (Lactobacillus delbrueckii, Leuconostocmesenteroides, Candida krusei, Saccharomyces cerevisiae) in an orange flavored carbonated soft drink was investigated. The MIC and MBC of extract ...
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In this research, anti-microbial activity of ethanolic extract of licorice root against food spoilage microorganisms (Lactobacillus delbrueckii, Leuconostocmesenteroides, Candida krusei, Saccharomyces cerevisiae) in an orange flavored carbonated soft drink was investigated. The MIC and MBC of extract against Lactobacillus delbrueckii was 0.7 mg/ml and 0.8 mg/ml respectively, and against Leuconostoc mesenteroides MIC and MBC were 0.9 mg/ml. Also, MIC and MBC against Candida krusei and Saccharomyces cerevisiae using microdillution method was equal to 0.8mg/ml. In this research an orange flavored beverage preserved with natural licorice root extract was formulated and parameters such as phenolic contents, changes in population of aerobic mesophilic bacteria, yeast and acid-resistant micro-organisms during storage time were evaluated. Concentrations of 1000, 1500 and 2000 ppm of licorice root extract and samples containing 1000, 1500 and 2000 ppm of licorice root + 50% benzoate was used to control growth of food spoilage microorganisms in the beverage. Samples enriched with licorice root and a blank sample (commercial sample) were kept at room temperature and microbial counts were monitored during 1, 10, 20, 30, 40, 50, 60, 70, 80 and 90 days. Results of microbial examinations showed that the use of licorice root extract preserved the orange flavor carbonated soft drink during 90 days storage. Also, phenolic compounds showed good stability during 90 days storage time.
Azadeh Ranjbar Nedamani; Yahya Maghsoudlou; Mohammad Ghorbani; Alireza Sadeghi Mahoonak
Abstract
Lycopene is a natural and dominant pigment in tomato with coloring and antioxidant properties, which nowadays the demands for its extraction enhancement from tomato and tomato products are increasing. In this study, the effect of pectinase enzyme pre-treatment at 2- 10 ml/kg and also washing with 94% ...
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Lycopene is a natural and dominant pigment in tomato with coloring and antioxidant properties, which nowadays the demands for its extraction enhancement from tomato and tomato products are increasing. In this study, the effect of pectinase enzyme pre-treatment at 2- 10 ml/kg and also washing with 94% ethanol at 60°C for 5 seconds was studied. In these conditions, treating with 10 ml/kg enzyme concentration at 90 minutes effective time resulted in maximum extraction of lycopene (279.5 mg/100g oleoresin) while for samples treated with pectinase and ethanol, maxmum extraction was 160.87 mg/100g olearesin. Also lycopene extraction yield from 100 g sample was 0.113609 and 0.089478 mg respectively. Totally in this study it was shown that pectinase treatment without ethanol treatment for extraction of lycopene is better in tomato waste.
Yasaman Etemadian; Bahareh Shabanpour; Alireza Sadeghi Mahoonak; Ali Shabani; Mohsen Yahyaee; Khodar Dordiee
Abstract
All of the food products are required to be packaged due to hygienic regard, storage, suitable transportation and preservation of quality and vacuum packaging is one of the prevention methods of spoilage. Hence in this study, some of the quality factores changes of Rutilus frissi kutum fillets storaged ...
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All of the food products are required to be packaged due to hygienic regard, storage, suitable transportation and preservation of quality and vacuum packaging is one of the prevention methods of spoilage. Hence in this study, some of the quality factores changes of Rutilus frissi kutum fillets storaged in vacuum and air packages were examined during 18 days in ice alike total volatile base-nitrogen (TVB-N), pH, water holding capacity (WHC), thiobarbituric acid reactive substances (TBARS), sensory characteristics and psychrophilic bacterial level. pH of the air packaged samples, rised with increasing psychrophilic bacterial load. Results of microbiological examination, indicated changes in bacterial of Rutilus frissi kutum fillets, has direct relation with sensory quality of packaged fillets in both vacuum and air packs, and shelf life and quality of vacuum packaged fillets was better as compared to air packaging, as cause fillets shelf life increase, 3 days more than air packaged fillets and effectively, controlled volatile bases-nitrogen level but alone was not able to controled lipid oxidation during ice storage. Therefore vacuum packaging cause shelf life time increase and better preservation of sensory, chemical and microbiological qualities of Rutilus frissi kutum fillets in ice.
Keywords: Vacuum packaging, Shelf life, Rutilus frissi kutum
