Food Technology
Rezvan Shaddel; Shadi Rajabi Moghaddam
Abstract
Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ...
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Introduction
Caffeine is one of the most common bioactive compounds in the world that can enhance mental and physical performance However its bitter taste has created challenges for the use of this compound in food. Nano-encapsulation technology, such as the use of liposomes, is one of the simplest ways to overcome this issue. In this research, caffeine was encapsulated in nanoliposomes coated with chitosan and then the drink powder enriched with caffeine nanochitosome was produced.
Materials and methods
In this research, pure caffeine powder was purchased and stored in dry environment at room temperature. Ethanol (96%) and acetic acid were obtained from Mojallali Company, Tween 80 from Merck Company (Germany), lecithin (P3556), cholesterol (C8667), and chitosan (medium molecular weight) purchased from Sigma Aldrich Company (Germany). Sugar, essential oil and citric acid used in the formulation of the drink were purchased from a local store.
First, nanochitosomes in ratios of 9:1, 8:2 and 7:3 lecithin-cholesterol, were prepared using thin-layer hydration method. Then, the particle size and zeta potential were measured to determine the characteristics of the produced particles. Encapsulation efficiency was measured for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios. The stability of the chitosomal sample with a ratio of 9:1 lecithin-cholesterol was evaluated through visual observation of precipitation formation and the amount of release of encapsulated caffeine during 60 days of storage at ambient temperature was calculated. FTIR was performed for each of the components of the wall of chitosomes, caffeine powder, chitosomal solution containing caffeine and chitosomal solution without caffeine with a ratio of 9:1 lecithin-cholesterol. Nanochitosomes with 9:1 lecithin-cholesterol ratio were used in the formulation of beverages due to having the smallest particle size, favorable zeta potential, the highest microencapsulation efficiency, and high stability during storage. The drink samples were prepared in different formulations (samples containing 3 and 5% free caffeine solution, samples containing 3 and 5% chitosomal caffeine solution and the control sample). Then, the drinks were evaluated in terms of sensory characteristics and other physico-chemical characteristics (pH, acidity, Brix degree, etc.). The drinks produced were turned into powder with a freeze-dryer machine, and two important characteristics of powdered products, i.e. water solubility index and their hygroscopicity, were evaluated.
Results and Discussion
The average particle size and zeta potential for different ratios of lecithin -cholesterol were obtained in the range of 133.3-443.6 nm and +40.96 to +48.36, respectively. The encapsulation efficiency for 9:1, 8:2 and 7:3 lecithin-cholesterol ratios were 91.2%, 86.18% and 79.09 %, respectively. The chitosomal sample with 9:1 lecithin-cholesterol ratio showed good stability during 60 days of storage at ambient temperature. FTIR results showed that caffeine was loaded in nanochitosomes. The results of the sensory evaluation of the prepared beverages showed the acceptability of the taste of the samples containing caffeine nanochitosome compared to the samples containing free caffeine, which indicates the success of chitosomal nanocarriers in covering the bitter taste of caffeine. The results of measuring the color of different drink samples showed that there is no significant difference between the color of samples. The results of measuring pH and acidity did not show significant differences between different drink samples. The results of measuring the solubility of different drink powder samples showed that the samples containing caffeine nanochitosomes have low solubility compared to other drink powder samples. Also, the hygroscopic amount of the drink powder containing caffeine nanochitosomes was lower than the other samples, which is considered as an advantage for powdered products.
The results obtained in this research showed that nanochitosomes are an efficient system in covering the bitter taste of caffeine. Therefore, with the production of caffeine nanochitosomes and its usage in the formulation of powder drinks, it is possible to produce energizing and desirable drinks without the need to use high amounts of sucrose.
Food Engineering
Setereh Ramezani; Mohammad Shahedi; Milad Fathi
Abstract
Global concern about human health and the increase the prevalence of chronic diseases in recent years lead to growing appeals for nutritious and healthy compounds, such as coenzyme Q10. Susceptibility to heat and lipophilic properties of coenzyme Q10 limit its utilization in food. Encapsulation is a ...
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Global concern about human health and the increase the prevalence of chronic diseases in recent years lead to growing appeals for nutritious and healthy compounds, such as coenzyme Q10. Susceptibility to heat and lipophilic properties of coenzyme Q10 limit its utilization in food. Encapsulation is a technology that protects bioactive ingredients from harsh environmental conditions and extends shelf life. The purpose of this study was to encapsulate coenzyme Q10 using complex coacervation by gelatin–basil seed mucilage and characterize physical, thermal and chemical properties of produced microcapsules. Response surface methodology was applied to determine the optimum level of the four formulation variables for maximum encapsulation efficiency, loading capacity and turbidity and minimum supernatant absorption. The optimum microcapsules had encapsulation efficiency of 83.69%, encapsulation load of 16.32%, turbidity of 0.979 and supernatant absorption of 0.227. The microcapsules were assessed by scanning electron microscopy, Fourier transform infrared spectroscopy, and differential scanning calorimetry. The results of FTIR confirmed the formation of coacervates. The thermogram of Q10 loaded microcapsule melting point was not observed at its melting point (50°C) due to its solubility in the oil phase and appropriate entrapment. Release behavior of Q10 was studied by different mathematical models. Microencapsulated Q10 was used to fortify milk and the results showed that the developed protein-carbohydrate microcapsules can be applied for protection of hydrophobic compounds.
Food Chemistry
Negin Jafarian; Afshin Akhondzadeh Basti; Hamideh Emtiazi
Abstract
Background and Objectives Natural preservatives extracted from herbs are important sources for bioactive compounds that can be used in protection of food products. Essential oils are aromatic oily liquids, obtained from plant material like flowers, buds, seeds, leaves, and roots. Unfortunately, ...
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Background and Objectives Natural preservatives extracted from herbs are important sources for bioactive compounds that can be used in protection of food products. Essential oils are aromatic oily liquids, obtained from plant material like flowers, buds, seeds, leaves, and roots. Unfortunately, most natural compounds are biologically instable, poorly soluble in water and they distribute poorly to target sites. Currently, some novel methods have been introduced in order to improve their stability and their bioavailability, among which is the use of liposomal encapsulation. Microencapsulation reduces reactivity with the environment (water, oxygen, light), decreases the evaporation or the transfer rate to the outside environment, promotes handling ability, masks taste and enhances dilution to achieve a uniform distribution in the final product when used in very small amounts. Essential oils, as natural extracted compounds extracted from plants, are unstable compounds with low water solubility and unable to achieve target cells. Essential oils encapsulation by nanoliposomes is a novel method for increasing their biological activity and protecting them from destructive factors. The aim of this study was production and optimization of nanoliposomes containing Z. teniur essential oil and investigating their antibacterial effects against pathogens (Staphylococcus aureus and Escherichia coli). Materials and Methods Lipid film hydration method was used to produce nanoliposomes containing Z. teniur essential oil. Soy phosphatidylcholine and cholesterol were the main wall materials and chloroform was used as the mixing solvent . The particle size of nanoliposomes and their zeta-potential were investigated using laser diffraction method. In order to determine the minimum inhibitory concentration and the minimum bactericidal concentration of Z. teniur essential oil against examined bacteria, serial dilution method was used. Also, antioxidant activity of free and nano-encapsulated essential oil of Z. teniur was determined by DPPH method. Results According to the results, highest encapsulation efficiency achieved by using 80:20 ratio of soy phosphatidylcholine to cholesterol in nanoliposomes’ wall structures. In general, by increasing the ratio of phosphatidylcholine to cholesterol, encapsulation efficiency was improved. Zeta-potential of nanoliposomes was equal to -5.3 mv and mean particle sizes were in the range of 94.7-119.9 nm. Results indicated that essential oil ejection from nanoliposomes has direct relation to the time of storage and after 30 hours, ejection rate will increase considerably. Ejection rate was higher in phosphate buffer pH=7.4 in comparison with phosphate buffer pH=5.4. Minimum inhibitory concentration and minimum bactericidal concentration of free essential oil against Escherichia coli was 100 and 175 (µl/ml) respectively. Although, Minimum inhibitory concentration and minimum bactericidal concentration of nanoliposomes containing Z. teniur essential oil were equal to 75 and 150 (µl/ml) respectively. Also, results shown that , minimum inhibitory concentration and minimum bactericidal concentration of encapsulated Z. teniur essential oil against Staphylococcus aureus were lower in comparison with free form of Z. teniur essential oil. Staphylococcus aureus (as Gram-positive bacteria) was more susceptible than Escherichia coli (as Gram-negative bacteria). Conclusion Encapsulation of Z. teniur essential oil by nanoliposomes led to improve antibacterial effects of essential oil against Staphylococcus aureus and Escherichia coli. Also, investigating of antioxidant activity showed that encapsulated Z. teniur essential oil in nanoliposomes was more effective than free form of Z. teniur essential oil in scavenging of DPPH free radicals. Using nanoliposome encapsulation technology can be an effective way for increasing the efficiency of natural antibacterial compounds and essential oils encapsulated in nanoliposomes are suitable alternatives for synthetic preservatives used in food industry nowadays. The use of liposomes containing Z. teniur essential oil can provide the necessary protection against growth of spoilage and pathogenic microorganisms such as Staphylococcus aureus and Escherichia coli in food products.
Food Engineering
Behnaz Vafania; Milad Fathi; Sabiheh Soleimanian Zad
Abstract
The aim of this research was to investigate the efficiency of nozzle-less electrospinning for encapsulation of ajwain essential oil (as a hydrophobic bioactive) using two hydrocolloids (chitosan/gelatin) in order to enhance its antioxidant properties and stability for food applications. Nanofibers were ...
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The aim of this research was to investigate the efficiency of nozzle-less electrospinning for encapsulation of ajwain essential oil (as a hydrophobic bioactive) using two hydrocolloids (chitosan/gelatin) in order to enhance its antioxidant properties and stability for food applications. Nanofibers were spun using chitosan/gelatin in ratios of 1:6, 1:8 and 1:10 and ajwain concentrations of 20 and 40%. Solution properties (i.e. viscosity and electrical conductivity) were measured. Encapsulation efficiency and loading capacity data illustrated an enhancement with increasing of essential oil concentration. Fibers diameter and morphology were studied by scanning electron microscopy (SEM). The chitosan/gelatin nanofibers with ratio of 1:6 containing 40% essential oil had the highest encapsulation efficiency (99.9%), loading capacity (39.9%) and the smallest diameter (146 nm). Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) proved that during electrospinning, no any chemical interaction was occurred between ingredients and differential scanning calorimetry (DSC) data showed that essential oil was well encapsulated in nanofibers. Antioxidant properties were analyzed by 2,2-diphenyl-1-picrylhydrazylradical and approved the efficiency of encapsulation for protection of antioxidants.
Food Technology
Farzaneh Esmaeili; Mahnaz Hashemiravan; Mohammad Reza Eshaghi; Hassan Gandomi
Abstract
[1]Introduction: Nowadays, there is a great tendency to consume functional foods, with special medicinal and extranutritional value in addition to basic nutritional properties. Foods containing probiotics and prebiotic compounds are classified in this category. Inulin is a water soluble storage polysaccharide ...
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[1]Introduction: Nowadays, there is a great tendency to consume functional foods, with special medicinal and extranutritional value in addition to basic nutritional properties. Foods containing probiotics and prebiotic compounds are classified in this category. Inulin is a water soluble storage polysaccharide and belongs to a group of non-digestible carbohydrates called fructans. Inulin is naturally present in some flowering plant species such as chicory and burdock root. The amount of inulin in these plants is in the range of 1 to 20% of the weight of the fresh plant. Pharmacological studies report that Burdock root contains significant amounts of the inulin as a prebiotic compounds, also exhibits a wide range of biological activities, specifically antioxidative, anti-inflammatory, and free radical scavenging activities. The aim of this study was to encapsulate the aqueous extract of burdock root and use it in a probiotic drink based on orange-carrot juice. Material and Method: The Burdock roots were obtained from the local medical plant market, Tehran, Iran. Orange and carrot juice were purchased from Nooshin and Tandis (Food Company, Tehran, Iran) respectively. Maltodextrin and gum Arabic were prepared from Merck, Germany. First, the plant roots were dried to 5.2% moisture and then its aqueous extract was extracted with the help of ultrasonication. Then burdock roots extracts were encapsulated by spray drying (microencapsulation) and freeze drying (nanocapsulation) using maltodextrin and gum Arabic as wall coating agents. Capsule properties including encapsulation efficiency, particle size distribution, moisture, density, structural properties, TPC and antioxidant were determined. Then the encapsulated extracts (at levels of 0.5 and 1%) and free extract were used in the formulation of probiotic orange-carrot juice and its effect on the survival of probiotic bacteria as well as physicochemical and sensory properties of the final product during 30 days in refrigerator (4±0.5 °C) were investigated. All experiments were carried out based on complete randomized design and the results represent the mean of at least three replicates. The data obtained were analyzed by the analysis of variance (ANOVA) using Minitab 16.0 statistical software. Significant differences between means were determined by Duncan’s multiple range test at a probability levels of P≤0.05. Results and Discussion: The results of encapsulation phase showed that Nanocapsules had higher efficiency and phenolic compounds content than microcapsules. The highest level of efficiency (92.75%) and phenolic compounds (0.385 mg GAE/g) and the smallest capsule particle size (14.33±0.22 µm) were observed in Nanocapsules prepared with gum Arabic. The SEM images showed that the produced capsules in terms of microstructure, had flaky/glassy and angular surfaces and did not have a regular shape. By adding different forms of the extract (free/micro/Nano) to the orange-carrot juice, it was found that its characteristics including viability of probiotics, formalin index, turbidity, viscosity and antioxidant activity were significantly enhanced during cold storage compared to the control (p<0.05). During refrigeration, turbidity, acidity and IC50 increased in all treatments, especially in the control sample, while other characteristics (including the viability of probiotic bacteria), showed a decreasing trend. Addition of different forms of burdock root extract did not have an adverse effect on the flavor and odor of the samples, so that, all treatments were acceptable. Therefore, based on the results of this study, it can be stated that encapsulated burdock root extracts, especially in the form of nanocapsulation, can be used to increase the viability of probiotics and enhancement the antioxidant activity of functional foods
Food Engineering
Maryam Azizkhani; Rafat Karbakhsh Ravari
Abstract
The objective of this study was to improve the survival of lactic acid bacteria (LAB) in Tarhana soup as a non-dairy matrix. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophiles were encapsulated in electrospun nanofiber mats fabricated from corn starch (CS) and sodium alginate ...
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The objective of this study was to improve the survival of lactic acid bacteria (LAB) in Tarhana soup as a non-dairy matrix. Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophiles were encapsulated in electrospun nanofiber mats fabricated from corn starch (CS) and sodium alginate (SA) and the protective effect of the nanofibers were investigated on the cells during the preparation of Tarhana and in the gastrointestinal tract. The moisture content of the control and nanofiber- loaded dried Tarhana samples was 8.75 and 8.71%, respectively; therefore, using nanofiber mats in the formulation had no significant effect
on the moisture content of the samples. A negative zeta potential value of -15.1 mV was found for LAB- loaded nanofibers. The nanofibers mats prepared from SA and CS mix showed a bead- free and clean structure with uniformity in size. The diameter size of most of the fibers ranged from 175- 338 with an average of 265 nm. Loading nanofiber mats with L. delbrueckii subsp. bulgaricus and S. thermophilus cells led to a uniform distributed beaded structure and the average diameter enhanced to approximately 763 nm. The viability of L. delbrueckii and S. thermophilus at the end of the electrospinning process was 92.82% and 95.83%, respectively, which indicating a slight loss in their population. Survival of nanoencapsulated S. thermophilus and L. delbrueckii was 93.50% and 89.16% respectively, while for free cells it was 85.3 and 76.4% that showed considerable protective effect of CS/SA fibers on the cells against dehydration of Tarhana medium. Nanofiber mats improved the stability of the cells against ordinary heat treatment used in preparing Tarhana soup. The survival rate of S. thermophilus was higher than L. delbrueckii subsp. bulgaricus and a significant difference was observed between the viability of free and nanoencapsulated bacteria. The survival of CS/SA nanoencapsulated S. thermophilus and L. delbrueckii subsp. bulgaricus was 83.25% and 80.21%, respectively, which is indicative of the significant protective effect of fibers on the cells against the heating process. The nanofibers also provided good stability for the cells in the gastrointestinal tract as 106 to 107 CFUg-1 of the cells were survived which is within the recommended level of potential probiotic dose to be effective. There was no significant difference in the color of all samples. Nanoencapsulation in CS/ SA nanofiber mats improved the protection of both LAB strains in simulated fluids of the stomach and intestine (Table 4). After continuous exposure to simulated gastrointestinal fluid, a significant loss of viable free LAB cells (higher than 4 log CFU/ml) was found while the population of S. thermophilus and L. delbrueckii subsp. bulgaricus encapsulated in CS/ SA nanofibers decreased only 0.45 and 0.37 log CFU after 120 min (p> 0.01), 0.93 and 0.80 log CFU after 180 min (p< 0.01), respectively. Tarhana soup prepared with probiotic– loaded nanofibers gained higher scores in terms of consistency, mouth feel, odor, taste, flavor, and overall acceptability attributes. Tarhana soup with nanofibers possessed much sour taste and flavor than samples prepared with free cells of probiotics. The results of the present study indicated that the protection obtained from CS/ SA capsules secured around106 to 107 CFU/g of the probiotic cells which are within the recommended level of probiotic dose to be functional in consumers’ body. Therefore, this product can be used by the consumers like vegetarians and lactose or milk peptide intolerants who do not consume dairy products but need potential fermented probiotic food.
Food Chemistry
Ensieh Nejat Pirsaraii; Eshagh Zakipour Rahimabadi; Aria Babakhani; Elham Aminpour Daphchahi
Abstract
Introduction: There is a growing body of evidence which long chain omega-3 fatty acids from seafood (Particularly EPA and DHA), are not only beneficial for general health and well-being, but also play a role in preventing of many important diseases. For these reasons, many health associations recommend ...
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Introduction: There is a growing body of evidence which long chain omega-3 fatty acids from seafood (Particularly EPA and DHA), are not only beneficial for general health and well-being, but also play a role in preventing of many important diseases. For these reasons, many health associations recommend to eat seafood at least twice weekly. Omega-3 fatty acid fortification is one of the fastest growing trends in the food industry. Dairy products are particularly suitable for enrichment with long chain n-3 PUFAs, in terms of popularity with consumers and special storage condition. So, this research was carried out to investigate the nutritional value and the fatty acid profile of Siahmezgi cheese fortified with encapsulated fish oil. Materials and Methods: For this purpose, at first, the microencapsulation process of fish oil with whey protein was performed at a ratio of 1:2 and the encapsulated oil was added in the process of producing Siahmezgi cheese. The treatments were as: control, treatment 1 (contained % 0.5 encapsulated fish oil) and treatment 2 (contained % 1.0 encapsulated fish oil). In this study, the determination of cheese fatty acid profile and sensory evaluation was performed at day 60 after cheese production and examination of peroxide value, thiobarbituric acid was performed at day 0, 30 and 60. Proximate analysis was calculated after cheese production, immediately. Results and Discussion: A total of 22 types of fatty acids were identified in Siahmezgi cheese samples. The ratio of unsaturated fatty acids to saturated fatty acids in treatments 1 and 2 were 0.78 and 0.83, respectively. The content of EPA and DHA in treatment 1 (0.09, 0.16 %) and treatment 2 (0.16, 0.47 %) were significantly more than control treatment (0.06 and 0.04 %) (p<0.05). The content of thiobarbituric acid in all samples was much lower than the allowed level. Sensory evaluation of control and enriched treatments of Siahmezgi cheese showed that all cheeses were generally acceptable by the judges.
Mahshid Shamloofar; Zahra Ghiasvand; Elham Payandan
Abstract
Introduction: Free radicals may cause lots of diseases in humans and oxidative degradation of lipids is a major factor limiting the shelf life of foods. The free radical reaction of lipid peroxidation is generally responsible for the deterioration of lipid-containing foods. Use of antioxidants during ...
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Introduction: Free radicals may cause lots of diseases in humans and oxidative degradation of lipids is a major factor limiting the shelf life of foods. The free radical reaction of lipid peroxidation is generally responsible for the deterioration of lipid-containing foods. Use of antioxidants during the manufacturing process can minimize the extent of lipid peroxidation. Phenolic antioxidant compounds can prevent the destructive effect of free radicals and their resulting mutation. Sunflower oil is widely used in nutrition as a source of essential linoleic (9-cis, 12-cis-octadecadienoic) acid. The present study explored the chemical constitution and antioxidant activity of Fleawort (Plantago ovate) extract and the effect of these natural antioxidants on sunflower oil. It is well known that edible oils used as cooking medium at high temperatures in the presence of oxygen are subject to therm-oxidation, polymerization, and hydrolysis, and the resulting decomposition products not only produce undesirable off-flavors, but can also decrease the nutritional quality of the fried product.
Material and methods: The present study was carried out in refined sunflower oil, free of additives, supplemented by pure concentration levels of normal and encapsulated extract of Fleawort (i.e., 200, 500, 700 and 1000 ppm) and one level of BHT (200) ppm .The doses of Fleawort extract were chosen in agreement with previous studies that have proved that the inhibitory effect on lipid oxidation increased with the antioxidant concentration In this research the phenolic content of the ethanol extract of Fleawort was determined by Folin–Ciocalteu method. The antioxidant activity of this extract was evaluated using DPPH• and ABTS methods. Furthermore, the oven tests including peroxide and thiobarbituric acid values were done at 65º C in sunflower oil.
Results and discussion: The results showed that different concentrations of this extract were effective in retarding the oil oxidation at 65ºC. Among the treatments, the 1000 ppm Concentration of encapsulated extract has higher antioxidant activity than other treatments during storage time. Based on the evaluation results of phenolic compounds in Plantago ovata extract, the amount of phenolic compounds of this extract will be increased according to the concentration of the extract. Although this index was the highest in treatment of EN 1000, there was no significant difference between the ordinary and encapsulated treatments (p>0/05). According to DPPH Evaluation Test for determining the antioxidant capacity of the samples, the highest amount of DPPH was seen in treatment of EN 1000 (p0/05). Also, based on the Restoration Power Test, treatment of EN 1000 had the most meaningful restoration power and in all concentrations of the extract and treatment showed the most meaningful restoration power (p< 0/05) . Treatments with concentration of 1000 ml/l had the maximum total antioxidant capacity and this treatment showed higher total antioxidant capacity compared to BHT treatment and numerically the total antioxidant capacity of all treatments of BHT was allocated to the treatments with concentration of 200 to 500 ml/l of fleawort extract. Peroxide value was used as indicators for the primary oxidation of sunflower oil. Hydroperoxides are the primary products of lipid oxidation. They are odorless and colorless, but are labile species that can undergo both enzymatic and non-enzymatic degradation to produce a complex array of secondary products. Determination of peroxides can be used as oxidation index for the early stages of lipid oxidation During the test time, both normal and encapsulated 1000 treatments had lower peroxide value through incubation time compared to all other treatments and 1000 EN treatment showed the lowest meaningful level of peroxide value (p
Elnaz Ghaem far; Seyed Mahmoud Reza Hojjati
Abstract
Introduction: Adding color to Foods can make them more appealing to consumers, to allow consumers to identify what taste to expect from a product, and to protect sensitive flavors from light. Color has always played a vital role in food selection and acceptance, and colorants are added to foods to alleviate ...
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Introduction: Adding color to Foods can make them more appealing to consumers, to allow consumers to identify what taste to expect from a product, and to protect sensitive flavors from light. Color has always played a vital role in food selection and acceptance, and colorants are added to foods to alleviate color lost during processing. Caramel color, from the palest yellow to the deepest brown, accounts for more than 80% (by weight) of all colorants added to the foods we eat and drink (Sengar, et al., 2014).Because of sensitivity of liquid colors to oxidation, light and heat and difficulties in their handling and incorporating, dried pigments have been developed. Microencapsulation is a technique to package materials in the form of micro- and nano-particles. There are different methods for encapsulation in the food industry. Freeze drying which has a long dehydration period, has been used as a simple technique in encapsulating water-soluble essential oils and natural aromas or drugs (Khazaei, et al., 2014). In this work, in addition to liquid caramel color production, encapsulation of liquid color with freeze drying technique through wall materials of maltodextrin and Arabic gum were carried out. The stability of microencapsulated color was then evaluated.
Materials and Methods: Rish baba grape and Kabkab date syrup were obtained from local market. Ammonium chloride, citric acid, sodium hydroxide, tween 80, Arabic gum were purchased from Merck (Germany). Glycine and maltodextrin were obtained from Sigma-Aldrich (USA) and Dextrose Company (Iran), respectively. In this study, the effect of factors such as type of catalyst (ammonium chloride-glycine), concentration of catalyst (0.5-2 molar), the pH of reaction (4-5), reaction time (60-120 minutes) on liquid color intensity of caramel produced from two natural sources of date and grape were investigated based on fractional factorial experimental design. For production of liquid caramel color, grape/date syrup was heated while being stirred to 65ᵒ C. Catalysts were then added to syrup and heated to 110ᵒC. water was added to reaction product and centrifuged. The solvent was removed by rotary evaporator (IKA HB 10, Germany).The resulting caramel color was stored under refrigeration at 4ᵒ C. In order to produce powder of caramel color, wall materials including Arabic gum and maltodextrin were dissolved in distilled water at ambient temperature to obtain 20% total solids concentration and stirred for 30 minutes at 60ᵒC. The mixture of liquid caramel color, tween80, and wall material solution was mixed in a ratio (w/w) of 1:4 (liquid caramel color: wall material) and stirred for 15 minutes. The mixture was then dried in a freeze dryer (ALPHA 1-2 LD PLUS, Germany) for 24 hours. The blank sample was prepared without wall materials and freeze-dried in similar conditions with other samples in 24 hours. Dried materials were collected and stored in brown glass bottles with screwed caps at 4⁰C until analysis. The powders were characterized using TGA/DSC thermogravimetric analysis (METTLER TOLEDO, USA), scanning electron microscopy (SEM) (TESCAN vegar, Czech Republic) and X-ray diffraction (XRD) (Billerica, MA, USA) to confirm the structural and morphological aspects of powders.
Results & Discussion: The results showed that the type of catalyst had no effect on the intensity of the colors and maximum color intensity (0.174 for color produced from grape and 0.15 for color produced from date) was obtained under these conditions: 120 minutes for reaction time, pH value = 4 and catalyst concentration of 2 molar. Results of thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC) indicated the increase of thermal resistance by microencapsulation process so that initial decomposition temperature for liquid form, without wall material, with Arabic gum and with maltodextrin for grape source were 114,138,162,185°C respectively and for date source were 113,131, 143, 180°C respectively. Results of Scanning electron microscope demonstrated that size of the powders were 11-55 μm. In conclusion, microencapsulation by freeze drying could be recommended as a suitable method for stabilizing caramel color.
Hassan Mirhojati; Parvin Sharayei; Reihaneh Ahmadzadeh Ghavidel
Abstract
The acidified ethanol extracts of dried barberry which have a relatively high anthocyanin content (376.28± 1.45 mg c3g/Kg dmp) were freeze dried using maltodextrin (MDX), polyvinyl-pyrrolidone (PVP) and mixture of MDX and calcium alginate (MDX-CaAlg) as a carrier and coating agents. The qualitative ...
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The acidified ethanol extracts of dried barberry which have a relatively high anthocyanin content (376.28± 1.45 mg c3g/Kg dmp) were freeze dried using maltodextrin (MDX), polyvinyl-pyrrolidone (PVP) and mixture of MDX and calcium alginate (MDX-CaAlg) as a carrier and coating agents. The qualitative attributes of the powders were characterized by their productively encapsulation efficiency, moisture content, bulk density, colour values (L*, a*, b*, C and H° ), particle size, total phenolic compounds (TPC), free radical scavenging activity of DPPH (RSA), ferric reducing-antioxidant power (FRAP) and minimized 50% of radical- scavenging activity (IC50). Scanning electron microscope was used for monitoring the structures of the powders. To determine the stability and half- life period of microencapsulated pigments, samples were stored under different storage temperatures (4◦C and 25◦C) at relative humidity 75%. Results showed that the encapsulated powder containing PVP 8% as wall material represented the best powder quality (p
Babak Ghanbarzadeh; Akram Pezeshki; Hamed Hamishekar; Mohammad Moghaddam
Abstract
Introduction: The encapsulation of hydrophobic nutraceutical compounds such as fat soluble vitamins in nanoliposomes is a potentially effective way to protect them from from light, oxygen and chemical degradation during the maintenance. One of the potential benefits of liposomal structures is encapsulation ...
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Introduction: The encapsulation of hydrophobic nutraceutical compounds such as fat soluble vitamins in nanoliposomes is a potentially effective way to protect them from from light, oxygen and chemical degradation during the maintenance. One of the potential benefits of liposomal structures is encapsulation of three water-soluble, fat-soluble and amphiphilic compounds and use of natural food ingredients such as lecithin with beneficial effects, in their production. In this study, the effect of lecithin-cholesterol concentrations on particle size, particle size distribution, encapsulation efficiency (EE) and physical stability of vitamin A palmitate loaded nanoliposome during the storage time were explored to get the optimized formulationMaterials and method:Materials: Phospholipid (L-α-granular Lecithin) with purity of 99% was obtained from Across (USA). Cholesterol with 95% purity was supplied by Merck (Germany). Other chemicals were analytical grade and procured from Sigma (Merck Chemical Co. Darmstadt, Germany).Methods:Nanoliposomes were prepared from different concentrations of lecithin–cholesterol (60:0, 50:10, 40:20 and 30:30 mg) by thin-film hydration–sonication method. Lecithin and cholesterol were dissolved in absolute ethanol and then dried with vacuum evaporator. Prepared dried lipid film hydrated by aqueous phase. The resultant suspension was mixed for some time (Hydration-dehydration). Due to existence of water inside the lipid film, osmotic pressure runs the water into bilayer membrane and causes separation of lipid film and then liposomes were produced. In this method, mixture of Multilamellar Vesicles (MLVs) and Small Unilamellar Vesicles (SUVs) liposomes were produced. Reduction in particle sizes of prepared liposomes was done by ultra sound probe sonicator. The average diameter and span value of the particles were determined using particle size analyzer (Wing SALD 2101, Shimadzo, Japan), at 25°C and was calculated according to the DeBroukere mean in the Equation (1):The span value is an index helpful to evaluate the particle size distribution and calculated applying the following Equation: Morphology of the nano-carriers was observed using trans- mission electron microscopy (Zeiss-Leo 906 TEM (Germany). To determine the zeta potential of nano liposomes loaded vitamin A, Zeta siyzer device (Nano-ZS -Malvern England) was used at 25◦C temperature. Estimation of encapsulated vitamin in nanoliposomes (%EE) was carried out using HPLC (Knauer,Germany) equipped with a UV detector, C-18(10 mm 25mm_4.6 mm) column and acetonitrile– methanol (70:30%,v/v) as mobile phase and was calculated using the below equation%EE= (Encapsulated Vitamin A)/(Total Vitamin A) ×100The stability of vitaminA loaded-nanoliposomes was assessed by determining the average particle size at 4 °C over storage time and studying the leak out of the vitamin from the nanoliposomes after one month(1,7, 15and 30days)of storage at 4 °C by the below equation%Stability = (Remained Vitamin A)/(Initial encapsulated Vitamin A) ×100Results and Discussion: Results showed use of sonication in completion thin-film hydration method, induced production of monomodular nanoliposomes with uniform distribution The particle size was in the range of 76-115nm and particle size distribution was monomodular (span= 0.6- 0.88). In agreement with particle size results, TEM image showed that the vesicles are in the form of small unilamellar vesicles by bilayer nature. In all concentrations of lecithin-cholesterol, obtained EE was low and by increasing the lecithin concentration, loading capacity of nano liposomes increased. By increasing the lecithin concentration, more vesicles are produced which causes increase in internal volume of liposomes and bio actives concentrate, consequently loading capacity of nano liposomes increased. By tightening of the membrane by cholesterol, entrapment efficiency of hydrophobic active compounds such as vitamin A palmitate reduces. Also probably existence of cholesterol in liposome membrane inhibits of rupture and changes in liposome membrane. Overall, increasing the ratio of cholesterol /lecithin had no significant effect on particle size but decreased encapsulation efficiency of vitamin A palmitate to 10.23%. Addition of cholesterol effected on stability of the particle size of nanoliposomes and also led to reduction encapsulation efficiency of vitamin A palmitate. Incorporation of cholesterol and vitamin A palmitate into the liposome structure was increased the zeta potential from -29 to -58 mv and improved electrostatic stability. 50-10 mg ratio of lecithin-cholesterol concentration was used for preparation of optimum formulation of nanoliposome by monomodular and small size distribution (76 nm, span=0.74) and encapsulation efficiency (15.8%). Stability of vitamin A in nano liposome with 50-10 mg lecithin-cholesterol, was almost low (32% reduction during storage time), may be due to increasing fluidity of membrane. Permeability of vitamin A into phospholipid chains causes reorientation of acyl chains which leads to fluidity of membrane and exit active compound from nano carrier and more its hydrolytic degradation and oxidation. While the use of thin film hydration method using ultrasonic waves, is successful way in producing nanoscale particles of vitamin A palmitate nanoliposomes that are stable and decrease over time, but due to low efficiency and low sustainability of encapsulation, use of other nanocarriers for encapsulating of vitamin A palmitate is recommended
Samira Tizchang; Mahood Sowti Khiabani; Reza Rezaeemokaram
Abstract
Nisin has numerous applications as a natural preservative in foods, including dairy product, canned food, processed cheese and milk. Several studies demonstrated that proteolytic degradation and the interaction of nisin with food components might result in decreased its antimicrobial activity. Encapsulation ...
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Nisin has numerous applications as a natural preservative in foods, including dairy product, canned food, processed cheese and milk. Several studies demonstrated that proteolytic degradation and the interaction of nisin with food components might result in decreased its antimicrobial activity. Encapsulation of antimicrobial peptides into nanoliposomes may offer a potential alternative to protect antimicrobials, enhancing their efficacy and stability for food applications. In first stage of this research, Response Surface methodology was used for optimization of nanoliposomes produced by heating method. A central composite design (CCD) consisting of 18 experimental run with three independent variables: phospholipid concentration (2-30 mM), stirring speed (500-1360 rpm) and processing time (30-90 min) were used and their effects on size of nanliposome were evaluated.In the next stages, stability of nanoliposomes was investigated during 2 month. The optimum operating conditions obtained from the quadratic form of RSM model for particle size were phospholipids 30 (mM), stirring speed 930 (rpm) and process time 90 (min). The results of stability indicated that samples in the range of 400 to 500 nm were stable up to 2 month (P > 0/05) but samples larger than 500 nm were unstable during 2 month but stable up to 1 month(P> 0/05).
Abbas Ahmadi; Seyed Ali Mortazavi; Elnaz Milani; Reza Rezaeemokaram
Abstract
In this study, frozen yoghurt was produced as a synbiotic product. A food product containing both probiotics and prebiotics is named as synbiotic or functional food. Lactobacillus acidophilus (La-5) as a probiotic bacteria was added to frozen yoghurt in two types; free and encapsulated, and its survivability ...
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In this study, frozen yoghurt was produced as a synbiotic product. A food product containing both probiotics and prebiotics is named as synbiotic or functional food. Lactobacillus acidophilus (La-5) as a probiotic bacteria was added to frozen yoghurt in two types; free and encapsulated, and its survivability was evaluated during 60 days storage at -18 °C . Also Fructo-oligosaccharide as a prebiotic compound was used for producing frozen yoghurt in different levels (0%, 0.4% and 0.8% (w/w)). The viable cell number in free state in samples with (0%, 0.4% and 0.8% (w/w)) Fructo-oligosaccharide was 3.8×109 cfu/ml, 3.5×109 cfu/ml and 3.8×109 cfu/ml and after 60 days of storage these numbers were decrease to 2×107 cfu/ml, 2.2×107 cfu/ml and 2.2×107 cfu/ml respectively. Whereas in encapsulated state, the viable cells in samples with (0%, 0.4% and 0.8% (w/w)) Fructo-oligosaccharide these numbers was 7.5×109 cfu/ml, 8.9×109 cfu/ml and 9.8×109 cfu/ml and after 60 days, these numbers were decreased to 2.13×109 cfu/ml, 2.5×109 cfu/ml and 2.9×109 cfu/ml.The results indicated that encapsulation of L. acidophilus could significantly (p
