Showing 50 results for Edible Coating
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Volume 4, Issue 4 (3-2016)
Abstract
The fatty acid composition and changes in silver carp fillet after flash frying, frozen storage and deep frying of was studied. For this purpose, fillets with edible coating and uncoated were tested. Fillets after flash frying for 30s, cooling, packaging and cooling were kept in freezer for three months, then deep fried. Flash frying and final deep frying increased the amount of total fat in fillets. The fat content of samples (5.07% at day 0) changed to 9.52 ± 1.97 and 7.54 ± 2.80 % after flash frying and to 9.33 ± 0.70 and 9.39 ± 0.24 % after final deep frying in uncoated and coated samples, respectively. Moisture content decreased after frying and increased after 3 months frozen storage (P<0.05). Twenty six saturated and unsaturated fatty acids were detected in samples. N-3/n-6 ratio was 3.37 in control samples. This ratio was 0.82 and 0.65 for uncoated and coated samples, respectively after flash frying and decreased to 0.66 and 0.28 after final deep frying. Atherogenic index (AI) and thrombosis index (TI) in day 90 after final deep frying in uncoated and coated treatments were 0.60, 0.53 and 0.57 and 0.69, respectively.
Seyed Ali Jafarpour, Sahar Alizadeh, S. Yeganeh, Reza Safari,
Volume 8, Issue 3 (9-2019)
Abstract
In this study, for the first time in Iran, the effect of edible coating of sodium alginate and whey protein in combination with innclulated cultivation of Pediococcus acidilactici and Lactobacillus plantarum bacteria on rainbow trout fillets was studied. Accordingly, chemical indicators such as pH, TVB-N, TBA and microbial laod at 0, 7, 14 and 21 days of refrigeration storage at 4C were investigated. Results showed that in all samples pH, TVB-N and TBA increased over time. In terms of microbial parameters, probiotic coating could reduce the number of TVC in coated fillets on day 21 compared to control treatment. However, the TVC level in all treatments at the end of the storage period was higher than the allowable range for human consumption (P<0.05). The number of LAB also increased during the storage period and there was a significant difference in coated treatments compared to control (P<0.05). The highest changes were observed in control treatment and the lowest changes were related the coated treatments. Overall, using higher percentages of sodium alginate containing probiotic bacteria can be recommended for better preservation of the fillet during the refrigerated storage.
Volume 8, Issue 30 (7-2011)
Abstract
The aim of this work was to study the effect of adding gellan gum and glycerol to film-forming solution on physical and mechanical properties of whey protein/gellan gum emulsion films and to produce edible coatings from whey and gellan gum and determine its effect on storage life of apricot. Whey protein coatings were prepared by dispersing 10% protein in distilled water; and plasticized with glycerol(Gly). Also gellan gum was added at different levels(0, 0/2, 0/4 and 0/6gr).
Therefore apricots were dipped in this coatings solution for 1 minute at 20˚C and air dried. Coated fruits together with the uncoated fruits(control) were placed in open dishes and stored at 4˚C and 85% RH for 1 months. Weight loss, total soluble solid(TSS), titrable acidity, pH, skin color, flesh firmness and overall acceptability of coated apricots and control were measured weekly.
The result revealed that the weight loss and changes in the quality parameters were much lower in coated apricots as compared with those. Color changes were also studied using a Hunter lab colorimeter. Finally results showed that the applications of whey coating increased overall acceptability, quality and storage life of apricot, while decreased its weight loss during storage.
The emulsion films were evaluated for physical and mechanical properties. Increasing the level of gellan gum in the films led to increase in Modulus(EM) and Tensile Strength(TS) but increasing gum to 0/6gr made less increase in Modulus(EM) and Tensile Strength(TS). About Elongation(EL), was observed increase too but in films that produced with 0/4gr gum, there was a slight decrease.
Volume 8, Issue 31 (8-2011)
Abstract
This study was designed to evaluate the effect of edible coating (Carboxyl Methyl Cellulose (0.17%) and Low Methoxyl Pectin (1.5%)), concentration of osmotic solution (10% salt, 10% salt + 5% sugar, 15% salt + 5% sugar and 15% salt + 10 %sugar) and immersion time (40, 60 and 80 minute) on osmotic dehydration of button mushroom. The result showed that the CMC coating improved the rehydration properties. Also, rehydration ratio increased as the immersion time and salt concentration in osmotic solution rose. The highest water loss related to CMC coating samples and the lowest solid gain achieved in control. Furthermore, the amount of water loss and solid gain increased with time and concentration of osmotic solution (p<0.01).
Volume 9, Issue 34 (6-2012)
Abstract
Antimicrobial packaging is a form of active packaging that could extend the shelf-life of foods and provides microbial safety for consumers. In order to control undesirable microorganisms on food surfaces, volatile and non-volatile antimicrobial agents can be incorporated into polymers. Incorporation of essential oils and other antifungal agents in edible films composition is an antimicrobial packaging that able to inhibit fungal growth on the pistachio and aflatoxins production.
The antifungal activity of Sage (Salvia officinalis) extracts against Aspergillus flavus in whey protein concentrate-based coating on pistachio kernels was investigated.
The antifungal effect of Sage extracts was investigated in culture media by direct method (well method) and application of whey protein concentrate (WPC) films as discs (disc method) incorporated with different concentrations of extracts. In order to evaluate the antifungal effect of extract in pistachio, kernels coated with different concentrations of extract inoculated with a culture media discs contain 9-day-old growing A. flavus colony and the growth rate of inoculated discs were measured during 1 week.
In experimental condition, minimal inhibition concentration was achieved by 155 ppm of ahcoholic extract (30 percent concentration). The results also showed that WPC coating incorporated with 4000 ppm of Salvia officinalis extracts on pistachio kernels inhibited A. flavus growth totally.
Paying regard to economical aspects of importance of contamination with toxigenic fungi in pistachio kernel suggest the application of Sage extract incorporated in edible coatings for toxigenic fungi growth and toxin production in foods.
Volume 9, Issue 35 (7-2012)
Abstract
Edible films and coatings are used to protect food products and improve their quality and shelf life. The objective of this study was to evaluate the effect of two methyl cellulose- based active coatings on the quality and storage life of tomato. Fruits were dipped in to active methyl cellulose (MC) coating (MC, glycerol and potassium sorbate) or active MC-palmitic acid coating (MC, glycerol, potassium sorbate and palmitic acid) for 1min at 20oC, then air-dried at room temperature and stored with uncoated samples at 15 oC and 80-85% RH for 21 days. At one day intervals, coated and uncoated fruits were removed and evaluated for weight loss, total soluble solids, titrable acidity, pH, skin color, firmness, failure energy, ascorbic acid content, yeasts and moulds count and overall acceptability. It was revealed that the coated fruits showed lower weight loss (up to 2.5 times), ripening rate, spoilage incidence (2-3 times) while, the skin color, ascorbic acid content, sensory quality and overall acceptability were higher in coated tomatoes when compared with control during storage time. However, non significant differences in the properties of tomato were observed by adding palmitic acid to the formulation of MC active coating.
Sakineh Kazemi, Ahmad Gharekhani, Amir Tokmechi,
Volume 10, Issue 1 (1-2021)
Abstract
Supplying fresh fish and sea products is accompanied with the problem of their rapid spoilage and short shelf life. Therefore, solutions which help increase this shelf life have always been valued. Accordingly, the aim of this study was to evaluate the effect of whey protein coatings containing four different concentrations (100,200,400 and 800 IU/gr) of nisin in perch fillet for storage in refrigerator temperature. Humidity tests, Peroxide Value, Thiobarbituric acid Index, microbial load, water activity and pH were performed over coated and uncoated samples. The results indicated that increasing the shelf life in all treatments led to an increase in peroxide value, Thiobarbituric acid Index, the load of bacteria, pH and water activity, this increase was less in coated samples than the uncoated ones. On the other hand, the findings showed that whey protein and nisin coating with the of concentration 400 IU/gr of perch fillet can add 16 days to increase the shelf life in refrigerator temperature in comparison with the uncoated samples. Based on our findings, it can be concluded that using whey protein coating containing nisin with the concentration of 400 IU/gr of perch fillet as edible coating can increase the shelf life in the refrigerator temperature.
Volume 12, Issue 48 (9-2015)
Abstract
Raisin is a principal traditional export product of Iran and has occupied a special position in the foreign trade of the country. During storage period, the product turns sticky and hard due to exudates syrup and moisture loss. To overcome this problem the application of edible coating suggests being of proper assistance. Edible coating may enhance the boundary layer resistance resulting enhanced shelf life of product. In this research the method of Accelerated Shelf Life Testing (ASLT) used for evaluation of storage and sensory properties (texture, colorو taste and overall acceptability) of raisin .Raisin was treated with coating materials based on lipid (glyceryl monoestearate and carnauba wax) with 150 ppm essential oil of thyme (thymus vulgaris) and stored at 20, 35 and 50oC for 12 weeks. During this period of storage sensory properties were evaluated and estimate the modeling shelf life of raisin. Results showed that coating, affect on texture and color significantly and caused increasing shelf life of raisin. Temperature and storage time also showed significant effects on total sensory attributes. Maximum shelf life (394 days) determined at 20 oC for carnauba wax coating with essential oil of thyme based on overall acceptability and linear regression and second order function had best fit with R2≥0.94 for all of treatments.
Volume 13, Issue 0 (11-2015)
Abstract
Volume 13, Issue 53 (5-2015)
Abstract
In order to improve the quality of shrimp (Litopenaeus vannamei) at refrigerated temperature (4±1°C), the shrimp samples were coated with solutions of chitosan (0, 0.5, 1, 1.5 and 2%), gelatin (0, 2 and 3%) and combination of them in 15 treatment group.Preservative effect of the coatings was evaluated by biochemical analyses, microbiological assays and physical measurements over 8th day of storage time. The findings indicated that 1%chitosan and 3%gelatin based coating was superior to others in preservation spoilage, inhibiting oxidation, improvement physical properties. The coating significantly (p≤0.05) reduced chemical spoilage as reflected in pH and total volatile basic nitrogen, microbial growth as reflected in total and psychrotrophic bacterial count and lipid oxidation as displayed in peroxide value and thiobarbituric acid compared to other treatment. Also, coated shrimps with the optimized coating were significantly (p≤0.05) indicated improvement in weight loss, color as reflected in a*, b* and L* values and texture as reflected in hardness compared to others. The optimized coating could enhance the shelf life of shrimp under refrigerated storage.
Volume 13, Issue 59 (0-0)
Abstract
To investigate the effect of edible coatings in retarding of bagutte bread staling, three types of coating formulations containing Sodium alginate, carboxymethyl cellulose and xanthan as hydrocolloids and sunflower oil, glycerol, water, starch and potassium sorbate were used for coating of baguette bread and The effect of these coatings on retarding of staling after 1,2 and 3 days of storage was investigated. The obtained results revealed that after 1 day of storage the mentioned coatings presented bread with similar freshness to that of control [ fresh sample]. After 2 days of storage, sodium alginate and xanthan coated samples acted similar in retarding of staling and after 3 days of storage, all the coatings did not have any significant difference with each other and also with control sample from staling point of view.
Volume 14, Issue 64 (6-2016)
Abstract
Volume 15, Issue 78 (8-2018)
Abstract
In this study, the effect of carboxylmethyl cellulose edible coating containing summer savory (Satureja hortensis) extract on the quality of Lethrinus nebulosus fillets during chilled storage was evaluated. Summer savory extract was extracted using ethanol 80% and its chemical compositions was analyzed using GC/MS system that totally 22 compounds were detected for summer savory extract and carvacrol was the main compound (28.67%) of extract according to GC/MS analysis. The fish fillets were divided into five groups: the control, CMC and CMC coating containing 0.5, 1 and 1.5% of summer savory extract and stored at 4±2°C for 9 days. During storage period, the analysis of biochemical (pH, TVB-N, TBA and FFA), microbial (total viable count and psychrotrophic count) and sensory evaluation (texture, odor, color and overall acceptance) for all samples were showed significantly changes (p<0.05). At the end of storage period, the sample treated with 1.5% of extract significantly had the lowest values of TBA, FFA and microbial growth compared to the control (p<0.05). Also, coated samples had the lower values of pH (p<0.05) and TVB-N than the control sample at the end of storage period. As regards to sensory evaluation, the coated samples had a longer shelf life (3 days) than the control sample, and the sensory properties of samples treated with extracts of 1 and 1.5%, significantly improved compared to the control on day 9 (p<0.05). Therefore, CMC coating enriched with summer savory extract represents a promising method for maintaining the quality of L. nebulosus fillets during chilled storage.
Volume 15, Issue 82 (12-2018)
Abstract
The modified atmosphere packaging and edible coating are applied to attained the objectives such as improving the quality of food products and increasing their durability. The impact of edible coating of aloe vera gel and packaging type on the quality of kiwifruit with Hayward cultivar was investigated. The test variables included type of coating in 4 levels (sample without coating (control), 10, 20 and 30% V-V of aloe vera gel) and packaging in two levels (normal air and modified atmosphere packaging 5% O2, 10% CO2 and 85% N2) and maintenance time in 4 levels (0, 3, 6 and 9 weeks). Kiwifruits were coated by immersion method. Then, they were packaged by three-layer plastic bags with 80 micron in diameter and kept in 20°C. All specimens were produced by three iterations and results were analyzed by SPSS. Tests included the determination of antioxidant capacity, measurement of total phenol content, determination of total acid ascorbic content, investigation of color changes and sensory evaluation. Results showed that the improved quality of specimens’ colors in modified atmosphere packaging together with the edible coatings was significant. Total amount of phenol and antioxidant capacity were larger in specimens with coatings with higher concentration and in antioxidant capacity. In specimens with higher concentration of aloe vera, the acid ascorbic was less destroyed. From the sensory evaluators’ point of view, the specimens coated under the modified atmosphere were ranked higher. In total, the modified atmosphere and coating of aloe vera gel improved the quality of the stored kiwifruit.
Volume 15, Issue 85 (3-2019)
Abstract
The effect of edible polysaccharide coating of Aloe vera and a packaging on physicochemical and biological properties of barberries during storage was examined. Barberries were treated with edible polysaccharide coating through immersion method and packaged under 0, 6 and 21% of oxygen concentration and maintained at 20 ºC for 12 weeks. During storage, moisture content, anthocyanin, color components and microbial characteristics were evaluated. The results showed that the effect of Aloe vera coating and packaging type on physicochemical and biological characteristics of barberries could be noticeable during storage time. Coating and packaging would reduce moisture loss, anthocyanin, brightness and redness. The number of aerobic microorganisms and amounts of mold and yeast in the samples treated with edible coating and packaging showed to be less than the control group during storage. Lastly, the results showed that coating with 10% of Aloe vera and vacuum packaging would further maintain color and anthocyanin, the main components of barberries.
Volume 15, Issue 85 (3-2019)
Abstract
The meat is susceptible to microbial and chemical contamination and microbial growth and lipid oxidation are the main causes of meat spoilag. Therefore the use of anti-oxidant and antimicrobial preservatives is essential. Allium Ursinum plant as a medicinal plant, duty to it's highly sulfur content has antioxidan and antimicrobial properies. In this research a solution of 3% Alginate containing 0, 0.5, 1 and 1.5% of Allium Ursinum extract coatings were investigaed to prolonge the shelf life of veal fillet in refrigerator condition. Veal fillets were coated with sodium alginate enriched by Allium Ursinum extract and mesophilic and psychrotrophic bacterial growth, moisture content, pH, TBA, PV and sensory characteristics evaluated for a period of 28 days periodically at 1, 7, 14, 21 and 28 days. The resulats of microbial assey showed that veal fillet coating with sodium alginate containing Allium Ursinum significantly decreased psychrophilic and mesophilic bacterial growth during 28 days storage at rfrigraed condition. Samples that coated with alginate coating- containning 1.5% Allium Ursinum extrac showed lower TBA, PV and pH values compared to control during the storage time. Samples treaed with sodium alginate containing 1% Allium Ursinum exract obatined the highest score of sensorial properties. According to the obtained results from the present study alginate-Allium Ursinum could be effective to increase the shelf life of veal fillet in refrigerated condition.
Volume 16, Issue 87 (5-2019)
Abstract
Biodegradable edible coatings, their enrichment with essential oils and their use on the surface of fruits are influential approaches that can reduce the problems of post-harvest management, thereby maintaining the quality of the produce. In this study, different concentrations of Arabic gum (0, 6 and 8% w/v) were used in combination with different concentrations of Shirazi thyme essential oil (0, 0.3 and 0.5% w/v), and their effects were measured with respect to various qualitative characteristics of fresh pistachio nuts which were evaluated for a period of 36 days under conditions of storage at a temperature of 3 ± 1°C. The results showed that the growth of mold and yeast and the growth of aerobic bacteria on the samples were significantly less than in other samples when using the 6% Arabic gum concentration enriched with the essential oil of Shirazi thyme at 0.3 and 0.5%. Also, adding the essential oil of Shirazi thyme (at 0.3 and 0.5%) to the formulation of Arabic gum (6%) managed to reduce the occurrence of water loss from the fresh pistacia and significantly reduced the weight loss from the samples. The addition of essential oil to the Arabic gum coating contributed significantly to the preservation of carbohydrates, chlorophylls, phenolic compounds, and antioxidants in the kernels of the fresh pistachios. Therefore, the use of edible coatings of 6% Arabic gum containing Shirazi thyme essential oil (at 0.3 and 0.5%) can maintain the quality and increase the shelf life of fresh pistachio.
Volume 16, Issue 87 (5-2019)
Abstract
In this research, the effects of whey protein concentrate based edible coatings containing different concentrations of natamycin and lysozyme–xanthan gum conjugate were investigated. For this purpose, Escherichia coli O157:H7 (as an indicator for gram negative bacteria and also resistant to commercial pasteurization), Staphylococcus aureus (as an indicator of gram-positive bacteria), and Penicillium chrysogenum were inoculated to ultrafiltrated white cheese surface and the microbial properties of cheese samples were evaluated during 28 days storing. The results showed that all coated treatments significantly reduced the growth of Penicillium chrysogenum. Natamycin-containing coatings have been more effective in reducing the mold population than lysozyme-xanthan-containing coatings. Coated samples containing 600 ppm lysozyme-xanthan reduced E. coli O157: H7 growth 2.09 log compared to control samples. Also, the growth rates of Staphylococcus aureus were lower in all samples treated with lysozyme-xanthan than control sample. The lowest growth rate of Staphylococcus aureus was observed in the coated sample containing 600 ppm lysozyme-xanthan on 28th day, with a microbial population of 2.60 logarithms. Unlike other treatments, the growth rate of Staphylococcus aureus in the sample coated containing 600 ppm lysozyme-xanthan was descending over 28 days. The results of this study showed that whey protein based edible coating can be used as a carrier of natamycin and lysozyme-xanthan in optimal concentration, for increasing the microbial quality of UF cheese.
Volume 16, Issue 88 (6-2019)
Abstract
The Mazafati date is one of the most important export products of Kerman province, which their quality characteristics may change during storage. The use of edible coatings is a new technique for increasing the shelf life of various agricultural products. The aim of this study was to investigate the effect of Aloe vera containing salicylic acid (2 mM) and green tea extract (0.5%) on physicochemical, microbial and sensory properties of stored dates at 4 and 25 °C for 150 days. The results of analysis of variance showed that the coating, temperature and time of storage had significant effects on the evaluated parameters (p <0.05). According to the results, the lowest weight loss was observed in samples coated with Aloe vera containing green tea extract and salicylic acid. This type of coating prevented significant changes in pH, acidity, total soluble solids (°brix), total and reducing sugar contents of date samples compared to the control during the storage period. During the storage period, the pH and total sugar content decreased, and acidity, total soluble solids and reducing sugar content increased. Total phenolic content did not have a clear trend during the storage period and its amount in the coated samples was significantly higher than the control. Aloe vera containing green tea extract and salicylic acid also effectively prevented microbial growth. In addition, panelists gave higher scores to dates coated with Aloe vera containing green tea extract and salicylic acid. The changes in physicochemical, microbial and sensory parameters in the stored dates at 25 °C were significantly higher than that stored at the temperature of 4 °C. In general, the use of Aloe vera containing green tea extract and salicylic acid, and storage at 4 °C is recommended due to the reduction of microbial growth and maintaining the quality characteristics of Mazafati date.
Volume 16, Issue 91 (9-2019)
Abstract
Abstract
In recent years, edible coatings have been extensively used for extension shelf life of fruits and vegetables. In this research, the effect of washing with citric acid (1%w/v) followed by coating with different concentrations of carboxymethyl cellulose (CMC;1, 1.5 and 2% (w/v)) in combination with ascorbic acid (AA; 1, 2 and 3% (w/v)) on postharvest quality of button mushrooms when stored at 4 for up to 15 days was studied. After treatment, mushrooms weight loss, soluble solid content, firmness, color, microbial and sensory quality were evaluated at 1, 4, 8, 12 and 15 days of storage. The result indicated that coating reduced weight loss and delayed changes of soluble solid content and color compared to uncoated control mushroom. Coatings had not remarkable effect on firmness of mushrooms. Sensory evaluation showed that the shelf life of mushrooms increased from 8 to 15 days. Washing with citric acid reduced total bacteria, yeast and mold counts. Among different coatings the combination of CMC 2% and AA 3% was more effective.
