Food Technology
Hoda Ghorbanzadeh; Jafar Milani; Ali Motamedzadegan
Abstract
IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become ...
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IntroductionWith the growth of the population and more demand for obtaining food and supplying the required food, the interest in the cultivation and consumption of edible mushrooms has increased. Since 1990, the world has focused on the mushroom production industry. In recent years, mushrooms have become one of the most important food and medicinal sources. One of the largest species of edible mushroom is button mushroom (Agaricus bisporus), which has high nutritional and medicinal value. Button mushroom has high nutritional value due to the presence of things such as fiber, carbohydrates, protein, amino acids, minerals, vitamins, etc., and it also has antioxidant, anti-cancer, and anti-diabetic properties. This food has shown good health properties for humans. The quality of button mushrooms is determined by their color, texture, and taste. Color is the first characteristic that is perceived by consumers. Browning is one of the main reasons for the loss of mushroom quality, which reduces the commercial value of mushrooms. One of the most used methods today is the use of edible coatings for perishable foods, these coatings almost prevent the penetration of oxygen, depending on the type of coating used, and reduce the loss of moisture during storage. Chitosan has functional characteristics such as antimicrobial and antioxidant properties, and as an edible film, it can be considered a very good carrier to be combined with antioxidant and antimicrobial agents.Materials and methodsTo make chitosan solutions, first, each type of chitosan (70% deacetylated, 80% deacetylated, 90% deacetylated, and 100% deacetylated) was weighed in amounts of 0.5g, 1g, and 2g. then it was dissolved in 100 ml of 0.5% acetic acid solution and stirred for 12 hours at a speed of 1000 rpm at room temperature to dissolve uniformly. After 12 hours, each sample It was centrifuged for 15 minutes at 6000 rpm at 25 °C to separate the undissolved material. Mushrooms were prepared freshly harvested, washed with water, and then excess moisture was removed. After sorting and screening in terms of size and approximate weight, the mushrooms were added to 0.5%, 1%, and 2% chitosan solutions without being sliced and were immersed in the solution for one minute. The control sample was immersed in 0.5% acetic acid solution for one minute. After that, the mushrooms were air-dried at room temperature for one hour, and at the end, their excess moisture was removed with a tissue. The mushrooms were placed in 18*14 size polyethylene zip-top bags and stored in a refrigerator at 4°C. The effects of chitosan coating on weight loss, mushroom color and browning index, enzyme activity, texture, and total phenolic compounds were studied.Results and discussionThe results indicated that in maintaining the amount of total phenol, controlling the peroxidase enzyme activity, the degree of firmness of the mushroom during storage and the amount of gumminess, the best treatment was chitosan with a deacetylation degree of 70%, while in controlling the weight loss, the activity of poly Phenol oxidase and sensory test, chitosan treatment with 100% and 90% deacetylation degree had better results, and in terms of browning index and texture, chitosan treatment with 80% deacetylation degree showed better performance. This study showed that the use of chitosan coating can be effective in maintaining the characteristics of edible mushrooms.ConclusionsThe spoilage of edible mushrooms happens in a short time, and the storage of mushrooms has become one of the most important things in mushroom production. Coating edible mushrooms is one of the suitable methods to increase the shelf life of edible mushrooms. In this research, chitosan with four degrees of deacetylation and three different concentrations was used as a coating for edible mushrooms. The results indicated that coating the mushroom with chitosan could delay the occurrence of spoilage and change its color or texture.
Food Biotechnology
Asad Abbaspour Anbi; Masoud Seidgar; Masoud Neyriz Nagadehi
Abstract
The present investigation was done to study the effects of Lactococcus lactis (L. lactis) subsp. lactis on the shelf life of the vacuum-packaged Oncorhynchus mykiss. Fish fillets were prepared and divided into 5 different treatment groups including control (distilled water), 2% and 4% supernatant, and ...
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The present investigation was done to study the effects of Lactococcus lactis (L. lactis) subsp. lactis on the shelf life of the vacuum-packaged Oncorhynchus mykiss. Fish fillets were prepared and divided into 5 different treatment groups including control (distilled water), 2% and 4% supernatant, and 106 CFU/g L. lactis subspecies lactis. The pH, Thiobarbituric Acid Reactive Substances (TBARS), Total volatile Nitrogen (TVN), and Peroxide Value (PV) of the fillets were determined on days 0, 5, 10, and 15 while maintained at 4˚C. Protein expression and destruction were analyzed using the SDS-PAGE. The organoleptic assessment was done using five expert sensory panelists. Contents of TBARS, TVN, pH, and PV were increased throughout the storage period (P <0.05). An increase in the concentration of supernatant caused a significant decrease in the content of TBARS, TVN, pH, and PV (P <0.05). The highest and lowest contents of TBARS, TVN, pH and PV on 15th day were belonged to the control (3.367±0.04 mg MDA/kg) and pure bacteria (0.70±0.02 mg MDA/kg), control (87.20±6.40 mg/100g) and 4% supernatant (40.79±0.61 mg/100g), pure bacteria (6.23±0.04) and 4% supernatant (5.44±0.07) and control (12.22±0.01 meq/kg) and 4% supernatant (3.08±0.06 meq/kg) groups, respectively. Protein destruction was lower in the fillet samples treated with pure bacteria and 4% supernatant. The highest scores of the odor, flavor, texture, and color were obtained for fillets treated with 4% supernatant, pure bacteria, pure bacteria, and 4% supernatant and pure bacteria, respectively. The results revealed that treating O. mykiss fillets with 4% supernatant and 106 CFU/g of pure L. lactis subsp. lactis can extend the shelf life of O. mykiss fillets.
Food Chemistry
Zeinab Ghasemi Arshad; Abdollah Ehtesham Nia; Eisa Hazbavi; Hassan Mumivand; Morteza Soleimani Aghdam
Abstract
IntroductionThe increase in people's awareness of the negative effects of chemical preservatives has led to more research on the antimicrobial effect of plant essential oils and their potential to be used as preservative compounds. Strawberry (Fragaria ananassa cv. qingxiang) is one of the ...
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IntroductionThe increase in people's awareness of the negative effects of chemical preservatives has led to more research on the antimicrobial effect of plant essential oils and their potential to be used as preservative compounds. Strawberry (Fragaria ananassa cv. qingxiang) is one of the most popular and widely consumed berries due to its taste, sweetness and healthy function. The taste of strawberry is related to its hardness, viscosity, sugars, protein, total soluble solid, titratable acidity content and minerals like P, K, Ca and Fe. It is a good source of polyphenolic compounds such as flavanols and has antioxidant activity. This, together with higher vitamin C content in strawberries, contributes beneficial effects on the maintenance of consumer health. Strawberry has higher antioxidant activities than orange, grape, banana, apple, etc. Strawberries are among the fruits sensitive to mechanical and physiological damage and have a fast metabolism and deterioration during the storage period. For this reason, it is necessary to use safe methods to control spoilage and maintain the quality of strawberry fruit during storage. Materials and Methods The experiment was conducted in a completely randomized design, in a 5 x 4 factorial scheme (5 treatments x 4 periods evaluated), with four replications The first variable was the type of material with different concentrations in five levels including 0, 0.3%, 0.6% carvacrol, the combination of chitosan with 0.3% and 0.6% carvacrol, and the second variable was storage time in four periods including 0, 10, 20, 30 days of storage. The harvested fruits were kept at 4°C and with a relative humidity of 90±5% and parameters such as weight loss, pH, firmness of the fruit tissue, acidity (TA), soluble solids (TSS) and taste index, vitamin C, phenol and flavonoid, fruit shelf life (number of days) during the storage period were investigated and studied. Results and Discussion The ANOVA results showed that the effect of the type of treatment and storage time on all investigated traits except for the firmness of the fruit texture was significant at the probability level of 1%. The fruits treated with the combination of chitosan and carvacrol 0.6% had more texture firmness, vitamin C, total phenol content and the amount of soluble solids and better shelf life than the control. In all four storage times, the highest content of total phenol (2.49 mg of gallic acid per 100 gr FW), total flavonoid (0.435 mg of Quercetin per 100 gr FW) and firmness (3.80 N) was related to the combined treatment of chitosan with carvacrol 0.6% and the lowest amount was related to the control. The firmness of the fruit tissue gradually decreased during storage, but this process was observed at a significantly slower rate in the treated fruits. ConclusionConsidering the increase of 10 and 12 days of shelf life post- harvest of the combined treatment of chitosan + 0.6% carvacrol compared to other treatments and the control, hence the application of chitosan pre harvest and the use of 0.6% carvacrol edible coatings can be recommended as a safe and low-cost strategy to increase the shelf life post harvesting of 'Parus ' strawberry cultivar.
Food Biotechnology
Siamak Gheibi; Amir Pourfarzad; Ahad Rastkar Allahverdizadeh
Abstract
Introduction Marinated chicken meat is one of the traditional foods in Iran which is an indoor and outdoor popular food in different areas of Iran due to its convenience and pleasant taste. It is also one of the authentic foods which is categorized in Iranian traditional kebabs. This product is ...
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Introduction Marinated chicken meat is one of the traditional foods in Iran which is an indoor and outdoor popular food in different areas of Iran due to its convenience and pleasant taste. It is also one of the authentic foods which is categorized in Iranian traditional kebabs. This product is constituted of fresh pieces of chicken meat, diced in different pieces, marinated with salt, lemon juice, verjuice, vegetables, saffron, spices, fruits and oil and then supplied as fresh and/or frozen form. After the seasoning, it is grilled using a skewer. Therefore, it is necessary to investigate its microbial load, shelf life, and quality changes during storage. To the best of our knowledge, there are no reports on the chemical and microbial properties of processed chicken meat used as a factor to predict its shelf life. Thus, the present study was designed to examine the relationship between physicochemical, microbial and sensory properties of the marinated chicken meat during storage using symmetric multivariate (determination of correlation coefficients and principal components analysis) and asymmetric methods (partial least squares regression). Materials and Methods In this study, 30 samples of marinated chicken meat were collected from restaurants. Then, the asymmetric method (completely randomized factorial and partial least squares regression) and symmetric method (coefficients of determination and Principal components analysis) were used for the study of chemical (aw, TVN, pH, O/R) and microbial (total count, Staphylococcus aureusand Escherichia coli) and organoleptic characteristics of samples on the storage days of 0, 3, 6 and 9.An aw meter was used to measure the aqueous activity (aw), an automatic Kjeldahl device was used to measure total volatile nitrogen (TVN) and a pH meter was used to measure pH and redox potential (O / R). The dilution method was used to count the total bacteria. The cooked meat and bird parker media were used to identify Staphylococcus aureus. The MPN method was used to identify Escherichia coli. Sensory evaluations were carried out by 10 trained panelists. All assessors of the internal sensory panel assumed the basic odor test and color vision test. Each sample contained 50g marinated chicken meat, which was given to panelists in plastic containers at room temperature. The color, odor and overall acceptance of the marinated chicken meat were assessed. Each evaluator randomly evaluated the samples and served drinking water before each evaluation. Each parameter was scored in a 5-point scaling ranging from 1 (lowest) to 5 (highest). The data on the physicochemical, sensory and microbial properties of marinated chicken meat were statistically analyzed using Minitab 15 software (Minitab Inc., State College, PA, USA). The mean values of the treatments were compared by Duncan's multiple range test at a confidence level of 95%. Each experiment was performed in three replications. The PCA and PLSR modeling were also performed on the datasets. Results and Discussion Results from the statistical analysis suggest that the microbial and chemical parameters of marinated chicken meat were greatly capable of predicting its shelf life. Determination coefficients, principal components analysis (PCA), and partial least squares regression (PLSR) models are able to extract relevant information and offer an easy and promising approach for the interpretation microbial and chemical properties of samples and their correlation with shelf life. The obtained results indicated that three parameters including pH, redox potential and total count had the highest correlation with shelf life, recommended as the predictive components. The results of measuring water activity in chicken meat samples during storage at refrigerator temperature showed that the aw parameter did not change significantly during storage time in the samples while the pH, TVN and O / R parameters were significantly affected. Changes in the total count, Staphylococcus aureus and Escherichia coli were also significant during refrigeration. Sensory evaluation experiments showed that all samples had no signs of spoilage until the sixth day. ConclusionThe obtained results indicated that three parameters including pH, redox potential and total count had the highest correlation with shelf life, recommended as the predictive components. Overall, we can produce a product with higher quality and shelf-life if high quality raw materials are supplied with suitable pH values and also, hygienic production is considered.
Mahyar Rad; Hamed Ghafori; Zohreh Gholami
Abstract
Introduction: Edible mushrooms are among the most perishable products that begin to lose quality immediately after harvest, and the short shelf-life of these products will cause problems when it comes to the marketing and distribution of these products in a fresh form. Edible coatings are a good tool ...
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Introduction: Edible mushrooms are among the most perishable products that begin to lose quality immediately after harvest, and the short shelf-life of these products will cause problems when it comes to the marketing and distribution of these products in a fresh form. Edible coatings are a good tool for prolonging the useful life of foods and increasing their quality without contaminating the environment. Materials and Methods: In this study, the possibility of increasing the shelf-life of a button mushroom using blanching followed by coating with carboxymethyl cellulose and sodium metabisulfite was studied. Independent variables included concentrations of carboxymethyl cellulose and sodium metabisulfite (0-2%) and storage time up to 16 days at 4 ° C. This experiment was designed on the basis of three-level factors consisting of 6 central points after 0, 4, 8 and 16 days of storage at 4°C. Factors determined on a button mushrooms included pH measurements, weight loss percentage, soluble solids, texture, color, browning level, total microorganisms count as well as mold and yeast count. Results & Discussion: The results of this study indicated that the sample coated with 2% carboxymethyl cellulose and 2% sodium metabisulfite resulted in an increase in pH level as well as soluble solids. In addition, the slightest color change, weight loss and reduction in tissue stiffness were observed in this sample. The sample coated with 2% carboxymethyl cellulose with 2% sodium metabisulfite had also the lowest total microorganisms count and the count of mold and yeast stored at 4 ° C after 16 days. Based on the results of this study, carboxymethyl cellulose and sodium metabisulfite coatings can be used as an appropriate coating agents for the preservation of organoleptic, chemical, microbial properties and shelf-life of button mushrooms.
Meysam Abediyan; Seyed Hamidreza Ziaolhagh; Ali Najafi
Abstract
Introduction. Apricot is a soft fruit that normally does not have any resistance to transportation and storage conditions. In addition, apricots are climacteric fruits, produces high levels of ethylene during ripening process and have a high respiration rate. For this reason, they are very susceptible ...
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Introduction. Apricot is a soft fruit that normally does not have any resistance to transportation and storage conditions. In addition, apricots are climacteric fruits, produces high levels of ethylene during ripening process and have a high respiration rate. For this reason, they are very susceptible to physiological and microbial spoilage and have a very short shelf life. Thus, it is difficult to export this product with good quality and low waste or it is very limited. Application of edible coatings could increase the storability of apricots and delay their spoilage. Edible coatings cover the surface of the fruit and function as a barrier against water vapor, respiration gasses, and microorganisms. The effect of different natural polymers as edible coatings on the quality and shelf life of different fruits has been investigated by many researchers. Chitosan has been used in the formulation of edible coatings to extend the shelf life of citrus, papaya, strawberries and grapes (Arnon et al. 2014; Ali et al. 2011; mehrzad et al. 2011; Mostofi et al. 2011). Apples coated with whey protein concentrate showed more lightness compared with non-coated ones (Perez-Gago et al. 2006). In most studies, the effects of single edible coatings on the quality of fruits have been studied. In this research the quantitative and qualitative changes during ripening and cold storage of apricots coated with different formulations of whey protein concentrate, sodium alginate and chitosan were studied.
Materials and methods "Rajabali" variety apricots were picked up at optimum maturity and damaged ones were separated. Edible coating solutions were prepared by dissolving different amounts of whey protein concentrate, sodium alginate and chitosan in to distilled water. Glycerol was used as plasticizer. The apricots were dipped in the prepared solutions with different concentrations for at least five minutes. Then they were stored for 35 days at 2°C. Some quantitative and qualitative characteristics of coated apricots, such as weight loss, acidity, color, texture, shrinkage, browning reactions, vitamin C, and microbial load were determined after 0 and 35 days of storage. The results were analyzed by response surface methodology based on central composite design with five replications at the central point.
Results & discussion. The statistical analysis of the results by central composite design (CCD) indicated that the different concentrations of whey protein did not have any significant effect on weight loss during storage. The weight loss decreased as the concentration of sodium alginate and chitosan increased. Chitosan and sodium alginate had an important role in maintaining firmness. The firmness of apricots were highest at the upper limit of sodium alginate (1%) and chitosan concentrations (2%). The b* (yellowness) and L* (lightness) values of the apricots were increased as the concentration of chitosan was increased and the concentration of sodium alginate decreased. No significant difference was observed between the a* values (redness) of apricots treated with different coatings. In addition, the acidity of the apricots was increased by increasing the concentration of chitosan and decreased by increasing the concentration of sodium alginate. Browning of the coated fruits was also increased as the concentration of chitosan was increased to 1%. Increasing the concentration of sodium alginate increased the shrinkage of the apricots at low concentrations of whey protein concentrate and decreased it at high concentrations of whey protein concentrate. It was also shown that increasing concentrations of chitosan would reduce microbial load. The optimization of the formulations with Design Expert software showed that the best formulation of edible coating for preserving apricots was 1.45% of chitosan, 1.25% of alginate, and 0 percent for Whey protein concentrate.
Tooraj Mehdizadeh; Hossein Tajik; Ali Mojaddar Langroodi
Abstract
Introduction: Meat is sensitive to microbial spoilage and chemical oxidation, so it is favorable to use a natural preservative with antioxidant and antimicrobial effects. The objective of this study was to prepare composite films from chitosan and starch containing pomegranate peel extract (PPE) and ...
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Introduction: Meat is sensitive to microbial spoilage and chemical oxidation, so it is favorable to use a natural preservative with antioxidant and antimicrobial effects. The objective of this study was to prepare composite films from chitosan and starch containing pomegranate peel extract (PPE) and Thymus kotschyanus EO alone and in combination to evaluate their effects on shelf-life characteristics, including physico-chemical (pH, aw and lipid oxidation), sensorial (color, odor and general appearance) and microbial (lactic acid bacteria, aerobic mesophiles, pseudomonas) on meat at 4°C for 21 days.
Materials and methods: Fresh pomegranate fruits (Punica granatum) were purchased from a local hypermarket. After separation, the peels were washed and dried. Thus 700 ml alcohol and 300 ml distilled water were added to 250g of powdered peel. The mixture was left in a shaker for 24 hr. After cooling and filtration using a paper filter, the solvent was removed in a rotary evaporator and the extract was stored at 4 °C until use. The Thymus kotschyanus was purchased a local market in Urmia. Hydrodistilation of dried parts of plant was performed in a Clevenger-type apparatus for 3 hr. Sodium sulfate was used for dehydration of the oil, then oil was filtered using 0.22 μm filters and stored in colored glass tubes in the dark at refrigerated temperature. Chitosan film solution was prepared by dissolving 1.5% (w/v) of chitosan in 1% (v/v) of glacial acetic acid solution with constant agitation using a magnetic stir plate during 24 h at room temperature. As a plasticizer, glycerol was added in the proportion of 30% (w/w) to chitosan powder, and the system was agitated for 5 min to complete homogenization. Starch solutions with concentrations of 3.5 % (w/v) were prepared by dispersing 27% amylose corn starch (Sigma-Aldrich Chemie GmbH, Steinheim, Germany) in distilled water and heating the mixtures on hotplates 95 ˚C during 30 min with stirring until it gelatinized, and then cooling to 40 ˚C. Composite films were prepared by mixing 100 mL of 2% chitosan solution with 100 mL of 3.5% starch solutions. For the films incorporated with the essential oils, tween 80 at a level of 0.2% w/v of essential oil was used as emulsifier. EO or hydro-alcoholic extracts were incorporated to the system at the level of 1% (v/v) of film form solution and homogenized in magnetic stir plate during more 5 min at room temperature. For microbial tests ten grams of each sample was diluted in 90 ml sterile 0.1 % ml peptone water (Merck, Darmstadt, Germany) and homogenized using shaker for 3 min at room temperature. Then, 0.1 mL of serial dilutions (0.1 % peptone water) of beef meat homogenates were transferred to agar plates. Pseudomonas were counted on Pseudomonas agar supplemented with CFC at 25 °C for 48 h (CFC, Merck, Darmstadt, Germany). Lactobacillus were enumerated on MRS agar (Merck, Darmstadt, Germany, Oxoid) incubated at 30 °C for 48 h. Finally, total mesophilic counts were determined using Plate Count Agar (PCA, Merck, Darmstadt, Germany), after kept for 2 days at 30°C. Level of lipid oxidation was investigated using thiobarbituric acid reactive substances (TBARS) method as described by Pikul et al (1989). Ten grams of sample was homogenized with 1 mL BHT (1 mg/mL) and 35 mL trichloroacetic acid (5%) in a blender. The mixture was filtered using Whatman no 1. Five mL TBA solution (0.02 M) of filtrate solution was added to 5 mL of filtrate solution and kept in a water bath at 100°C for 60 min to expand the malondialdehyde–TBA complex. After cooling the tube, the absorbance of the samples were determined at 532 nm. The pH values were determined using a digital pH meter. A 5 g of beef meat sample containing 25 ml of distilled water was homogenized for up to 1 min. The sensory analysis of meat samples was carried out with 10 trained PhD students. After preparation of treatments, the samples were offered to each panelist separately. Fresh beef meat was used as a control. Panelists were asked to evaluate texture, color, flavor and odor and overall acceptance on a nine-point Hedonic scale, with 9 being so good and 1 being so poor.
Results and discussion: The incorporation of PPE and EO into composite film showed that aerobic mesophiles and lactic acid bacteria were the most sensitive and resistant groups to films by 7.11 and 6.92 log cycles reduction after 21 days’ storage, respectively. In addition, meat wrapped by 1% PPE films had the lowest degrees of lipid oxidation (1.11 mg MDA/kg samples) which was 61% lower than the control samples (2.90 mg MDA/kg samples). This study showed that starch-chitosan composite films containing of pomegranate peel extract and Thymus kotschyanus EO was significantly antibacterial properties, while shows the higher antioxidant effect. PPE also improves some physical properties of the film. Our results indicated that incorporation of pomegranate peel extract (PPE) and Thymus kotschyanus EO as a natural antibacterial agents have a potential to prolong the shelf-life of meat.
Zeinab Noori Hashemabad; Bahareh Shabanpour; Hamed Azizi; Seyed Mahdi Ojagh; Alireza Alishahi
Abstract
Introduction: The importance of maintenance and supply fresh fish instead of frozen due to the consumers interested in fresh fish is highly regarded. Titanium dioxide is a non-toxic nanoparticle that the American Food and Drug Administration approve its using at levels that are in contact with food. ...
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Introduction: The importance of maintenance and supply fresh fish instead of frozen due to the consumers interested in fresh fish is highly regarded. Titanium dioxide is a non-toxic nanoparticle that the American Food and Drug Administration approve its using at levels that are in contact with food. The antimicrobial and anti-fungal effects of this nanoparticle have been proven in a wide range of microorganisms (Saito et al, 1999).The use of titanium dioxide nanoparticles in polyethylene and polypropylene coatings has been investigated. The results showed that this nanoparticle, in addition to reducing the oxidation content of the package, could be effective in reducing silicone recovery of polyethylene and polypropylene in nature (Manangan et al, 2010). Rainbow trout is one of the most widely consumed breeding fish in Iran. Due to the high production and consumption of this fish, it is vital to take the necessary measures to maintain quality and increase its shelf-life. Therefore, this research was conducted to investigate the effect of titanium dioxide nanoparticle polyethylene packaging on quality and shelf-life of rainbow trout fillets during storage in a refrigerator.
Material and methods: Chemical (Peroxide value (PV) )Pearson,1997(., Tiobarbioritic acid (TBA) (Egan et al., 1997(, total volatile basic-nitrogen (TVB-N) (Pearson, 1997), pH), microbial (Total viable, Total viable counts, psychrophilic counts, lactic acid bacteria and Enterobacteriaceae) and Sensory analysis of samples was calculated and determined. The results of ANOVA using SPSS 16 software analysis and comparison of data using Duncan's multiple range test was 0.05 Sensory evaluation and analysis of non-parametric Mann-Whitney U test was used to test.
Result and Discussion: The process of microbial changes in the rainbow trout fillet was increased, except for the psychrophilic bacteria that were in the packaged nanocomposite treatment until the 4th day of the growing trend and then until the end of the period was reduced. Nanocomposites containing titanium dioxide containing nanoparticles prevent the growth of pseudomonas. (Bodaghi et al, 2013).The total amount of all chemical factors during the storage period showed an increasing trend in both treatments except for the factor observed in the packed sample. The results showed that in the control sample, the sensitivity rating on the day 8 was kept to a limit of less than 4, while in the sample packed with the nanocomposite until the 16th day, the points were less than the limit and the color score on day 12 Limiting receipts. Fat oxidation and microbial decomposition, and the production of esophagus combustion agents and fish tissue were changed. The antioxidant and antimicrobial effects of the packaged sample resulted in prolonging the shelf life and maintaining the quality of the fillets until the 16th day. Sensory, chemical and microbiological analysis results showed that the rainbow trout shelf life in nanocomposite packaging is suitable for 16-18 days.
Bahareh Shabanpour; Mansoureh Neirizi; Zeinab Noori Hashemabad
Abstract
Introduction: Surimi is one of the procedures that nowadays it is suggested to increase the consumption of fish such as silver carp (Shabanpour et al., 2008). Surimi is washed and minced fish meat myofibrillar concentration of proteins, this would wash out most of the soluble material in surimi (Sultanbawa ...
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Introduction: Surimi is one of the procedures that nowadays it is suggested to increase the consumption of fish such as silver carp (Shabanpour et al., 2008). Surimi is washed and minced fish meat myofibrillar concentration of proteins, this would wash out most of the soluble material in surimi (Sultanbawa & Li- chan, 1998). Raw fish freshness and quality of the most important factors affecting the quality surimi (Phatcharat et al., 2006). Low-temperature storage, especially storage in ice, one of the most suitable criteria for refrigeration methods and maintain the quality of fish (Benjakul et al., 2002), although changes in chemical, biological and physical on the ice completely stopped when maintenance is not are (Benjakul et al., 2003; Riebroy et al., 2007). The aim of this study was to evaluate the maximum duration of storage of silver carp in ice for surimi production with high quality and efficacy during storage on the quality of surimi made from these fish when kept in ice. Materials and methods: Silver carp ((Hypophthalmichthys molitrix fish at intervals of 0, 4, 8, 12 and 16 days after initial preparations into surimi process and the assessments of microbial (bacterial load and total bacterial load of cool), chemical and sensory respectively. Chemical experiments: Thiobarbituric acid method Siripatrawa and Noipha (2012), volatile nitrogen bases by Goulas and Kontominas (2005), protein solubility and humidity values of pressure Rawdkuen et al (2009), pH Suvanich method and colleagues (2000). White index by Kristinsson et al (2005) using a colorimeter Lovibond CAMsystem500 model model was calculated and determined. Measuring the properties of gel production: Preparation Gel by (Jafarpour & Gorczyca, 2008) and evaluation gel by (Lanier, 1992) were done. Microbial testing of samples was done according to (Sallam, 2007) Sensory analysis of samples: To assess quality parameters include color, odor, taste and overall acceptance of samples of hedonic scale (slightly modified) was used. In order to test a panel group consisted of 10 people consisted of very good quality Grdydstvh use with a score of 7, well with a score of 5, acceptable with a score of 3, bad and very bad rating with a score of 0 is 1 (Shabanpour and et al., 1386). Data analysis: The results of ANOVA using SPSS 16 software analysis and comparison of data using Duncan's multiple range test was 0/05 Sensory evaluation and analysis of non-parametric Mann-Whitney U test was used to test. Results and Discussion: The research results showed that the solubility of proteins soluble salt (because ice crystals formed during cold storage the concentration of mineral salts in muscle cells increases), protein solubility, chemical indicators, microbial and sensory surimi (Due to raw materials oxidation (hydroperoxides) secondary unstable and prone to decomposition products such as aldehydes), White indicator, the ability to get qualitative rating factors evaluated (taste, odor, color and overall acceptability) negative trend and Percent moisture (Because denaturation of proteins myofibrils), microbial changes, changes in pH (Due to volatile nitrogen bases), changes in the volatile nitrogen bases ( Due to microbial growth) and TBA (Because tissue damages) has increased. Sensory and microbiological analysis results showed that the shelf life of silver carp in ice for surimi production is suitable for 8 days.
Malahat Safavi; Majid Javanmard
Abstract
In this study, the effects of coating with whey protein concentrate (7.5% w/v) alone and/or in combination with rice bran oil (0.2, 0.4, 0.6 g in 100 ml coating solution) and Zataria multiflora extract (1 and 2 μL in 100 ml coating solution) on the quality attributes and egg shelf life were carefully ...
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In this study, the effects of coating with whey protein concentrate (7.5% w/v) alone and/or in combination with rice bran oil (0.2, 0.4, 0.6 g in 100 ml coating solution) and Zataria multiflora extract (1 and 2 μL in 100 ml coating solution) on the quality attributes and egg shelf life were carefully observed and analyzed. Weight loss, Haugh index, yolk index, pH, air cell depth, shell strength and the impact of this coating on the microbial load of the eggs surface were studied at the end of each week (during the 4 weeks of storage in a room environment temperature and humidity). After 4 weeks of storage, it was observed that the weight loss in all of the treated eggs with whey protein concentrate and 0.2 gr of rice bran oil (experimental group) was significantly lower than that of the control group(P<0/05). With regard to Haugh index and yolk index, egg shelf life increased about 4 weeks compared with the control samples. Haugh Index changes revealed that the coated samples remained at grade A after 3 weeks of storage, while the control samples were relegated from grade AA to B after one week. Haugh and yolk Indices in all coated eggs were more than those of the control group. In the coated groups, Haugh and yolk indices of the coated samples with whey protein concentrate and 0.2 g rice bran oil and with whey protein concentrate and 0.2g of rice bran oil and 1 micro liter of Zataria multiflora extract were more than those of the other coated eggs and the control group eggs. PH values of the control group were higher than those of the coated groups during the storage of the eggs. The shell strength of the coated group was more than that of the control group (uncoated) and in coated samples, whey protein concentrate and 0.2 gr of rice bran oil coated samples had high shell strength. In the other treatments no significant differences were observed. The depth of the air cell of the coated groups was determined to be less than that of the control group during the storage period. The minimum inhibitory concentration was 1 μL of Zataria multiflora extract. The results showed that 1 μL concentration of Zataria multiflora extract reduces the microbial load of the egg shell surface to 87% and 2 μL reduced total bacterial load to zero. In sensory evaluation, from evaluator point of view, the coated eggs had more overall acceptance than the uncoated group (control), and in the treatment group coated eggs, those containing a low percentage of rice bran oil had higher overall acceptability. In conclusion, coating as a practical and cost effective method can maintain the quality parameters of eggs and lead to durability of supply conditions in addition to the product marketability.
Amir abbas Omidfar; Esmaeil Atayesalehi; Zahra Sheikholeslami
Abstract
Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt ...
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Introduction: Low quality and short shelf-life are the most important reasons for bread waste. Statistics show that each Iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. Previously barley malt was used as an additive to improve the quality and shelf life of bread (including Barbari bread). The most common type of the malt used in the world is barley malt. This is because of the utilization of most of the malt product in the world, including to produce beverages based on malt, particularly alcoholic and non-alcoholic onesand considering that the malt made from barley grains has the best quality among the other cereals to produce these products.Therefore, discussion on other malted cereals would be find less in the literature especially corn malt (which has not a good quality to produce malted beverages). On the other hand, corn is the main cereal widely consumed in the world after wheat and rice. The purpose of this study was to produce Barbaribread usingcorn malt (powder or extract) as an additive to increase shelf-life, volume and softness, as well asimprove the sensory characteristics (staling, total appearance, softness, texture, brain color, crust color, crust appearance, flavor and odor). Materials and methods: For this purpose, bakery flour with 85% extraction rate, Dent corn (Zea mays var. Indentata), Saccharomyces cerevisiae as an active dry yeast, malt extract or powder and other additives, used in the formulation of Barbari bread. To evaluate the sensory characteristics, the bread samples were analyzed by 15 trained referee. The results were based on a factorial arrangement with two factors completely randomized design that the first factor is type of corn malt (powder or extract) and the second one is amount of corn malt (in four levels of 0, 0.5, 1.0 and 1.5 percent) was evaluated. Results & Discussion: The resultsshowed that the treatment with 1.5 percent extract corn malthas the highestspecific volume(with an average of 4.5) and thetreatment with 1.5 percent powderhas the lowestspecific volume(with an average of 3.67). And just the treatments with 1 and 1.5% malt extract in compared with the control sample showed significance differences (P
Sepideh Amirabadi; Arash Koocheki; Mohebbat Mohebbi
Abstract
In this research, different concentrations of xanthan and Lepidium perfoliatum seed gums (0.1, 0.2 and 0.3%) were used to improve the quality and shelf-life of chiffon cake. For this purpose, specific gravity and apparent viscosity of batter, and the volume, specific volume, moisture, sensory and texture ...
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In this research, different concentrations of xanthan and Lepidium perfoliatum seed gums (0.1, 0.2 and 0.3%) were used to improve the quality and shelf-life of chiffon cake. For this purpose, specific gravity and apparent viscosity of batter, and the volume, specific volume, moisture, sensory and texture properties, crumb and crust color were examined. To investigate the effect of gums on the shelf-life, all cakes were stored for sixth days. Results showed that there were a positive correlation between viscosity of batter and cake volume. Both gums improved chiffon cake properties after removing from the oven and during storage. It was found that using 0.1% xanthan gum increased the cake volume, cohesiveness and sensory scores, decreasing firmness and moisture loss during storage of cake.
Sanaz Ojnordi; Majid Javanmard; Simin Asadollahi
Abstract
Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been ...
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Due to environmental risks generated by application of non-degradable and synthetic films, many researches have shown increasing tendency to edible coatings for storing food such as fruits and vegetables. Whey protein is considered one of the most common sources of edible coatings and its use has been studied in the current research. In this paper, the simultaneous effect of coating with whey protein and Zataria multiflora Boiss extract on the quality of peach kept in refrigerator has been studied. According to response surface methodology, were measured 20 treatments repeating 6 times in the center point and effects of the three factors including whey protein (2. 5 to 5 gr), Zataria multiflora Bioss extract (0 to 500 μL) and glycerol (0. 375 to 2. 25 gr) on the physicochemical characteristics, fungal decay and organoleptic traits of peach, were investigated in the condition 5±2 ̊C and 80% relative humidity during 21 days of storage. According to the results, by increasing Zataria multiflora Bioss extract concentration and whey protein of the coating, microbial decay and weight loss of the fruit was reduced and texture and soluble solids were conserved. Peel colour changes of the coated fruit was not significant compare to control and the coated samples had a light and bright colour. Coating peach resulted in natural ripening of the fruit and the coated fruits were softer and juicier than the fruits without any coating. The coating formulations had significant effect on TSS and TA. Optimized points of variables for achieving a coating with the maximum effect on shelf life improvement of peach (Prunus Persica cv. Anjiri) are: whey protein 4. 7475 gr, Zataria multiflora Bioss extract 498. 00 μL and glycerol 0. 6212 gr.
