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Okra is a vegetable crop with high nutritional value that quickly loses its quality and decay after harvesting. This research aimed to investigate influences of calcium chloride concentrations combined with chitosan coating on the quality characteristics of okra pods during post-harvest. Okra pods were immersed in different concentrations of calcium chloride (0%, 1%, 2%, 4%) and then covered with chitosan (0, 0.5, 1 and 1.5%). Physicochemical analysis including: physiological weight loss, firmness, titratable acidity, total soluble solids, ascorbic acid content, total phenol content, and visual appearance and decay rate were performed at 4-day intervals for 16 days. The results showed that during storage, weight loss, soluble solids, and decay rate increased and firmness, ascorbic acid, total phenol content, titratable acidity and visual appearance showed a sharp decrease. Chitosan coating containing calcium chloride was significantly effective in maintaining the quality characteristics of okra. Among the investigated treatments, a combination of 2% calcium chloride and 1% chitosan was the most effective method to maintain the highest overall quality index score of okra pods stored at 4°C for up to 16 days. This treatment also significantly reduced weight loss and maintained ascorbic acid, total phenolic content, titratable acidity and visual appearance, and delayed increase in soluble solids and decay. [ABSTRACT FROM AUTHOR]

This work's main objective was to investigate the gum Arabic effect on reducing oxidative stress in bell peppers during ripening. Gum Arabic in 6, 9, 12, and 15% aqueous solutions was applied as an edible coating before storage on mature bell peppers stored at 8°C and 90-95% relative humidity for 28 days. The fruits that were coated with 12% gum Arabic had the lowest rate of decay, weight loss, total carotenoid content, and peroxidation of membrane lipids, as well as the highest total antioxidant capacity, total phenol, ascorbic acid, and antioxidant enzyme activity (superoxide dismutase, peroxidase, and catalase) during storage compared to the control without coating and the fruit treated with 6 and 9% gum. Still, there was no statistically significant difference with the fruit treated with 15% gum Arabic except for the total carotenoid content. The amount of peroxidation of membrane lipids showed positive and high correlation coefficients with decay (0.93**) and physiological weight loss (0.89**), but with antioxidant capacity (-0.93**), ascorbic acid (-0.94**), total phenol (-0.92**), activity of SOD (-0.96**), CAT (-0.87**) and POD (-0.86**) correlation. It was negative and high. The results showed that the use of 12% gum Arabic as an edible coating can delay oxidative stress and decay and maintain the antioxidant properties of the fruit for up to 28 days during storage at 8 degrees Celsius. [ABSTRACT FROM AUTHOR]

The use of edible coatings to preserve fruits and vegetables during storage has attracted increasing attention. Also, salicylic acid has been used as an anti-ethylene and antimicrobial compound to improve the postharvest life of some crops. In this study, the effects of different concentrations of salicylic acid (0, 1, 2, and 4 mM) and sweet basil mucilage (0, 0.1, 0.2, and 0.3 percent) on the postharvest quality of okra during storage at 10 °C were evaluated. The results showed that increasing the storage time decreased the quality characteristics of okra. Sweet basil mucilage and salicylic acid treatments were significantly effective on maintaining the quality characteristics of okra. The highest levels of fruit firmness, soluble solids, titratable acidity, ascorbic acid, visual appearance, and the lowest weight loss were obtained in the 0.3% sweet basil mucilage and 4 mM salicylic acid treatments. Okra without coating and salicylic acid treatment completely lost its appearance quality during 16 days of storage but okra treated with high concentrations of salicylic acid and mucilage had good quality and required marketability. As a result, sweet basil mucilage and salicylic acid can be used as effective treatments to maintain the quality aspects of okra for a more extended period. [ABSTRACT FROM AUTHOR]

Key lime juice can be a non-fermenting product with high acidity and a rich source of ascorbic acid and phenol compound. In order to maintain the quality of the product, it is important to choose a suitable method for processing this food. The use of modern non-thermal methods to produce high quality products should be considered. In this research, by designing and constructing a continuous pulsed electric field (PEF) system, the effect of this method on the degradation of pectin methyl esterase (PME), ascorbic acid, total phenol compound, cloudiness index, color changes and sensory evaluation in key lime juice is discussed. In this research, a bipolar square wave of 10 microseconds and a constant frequency of 1000 is used. In the processing chamber of this device, two cases of stainless steel with length and thickness of 10 and 0.5 ml, respectively, were used. Key lime juice was processed for 500, 571, 666, 800 and 1000 microseconds with Field intensity of 22.22, 33.33, 44.44 and 55.55 kV per cm. In general, by increasing the field from 22.22 to 55.55 kV / cm at a constant time, the process of reducing the degradation of PME enzyme is normally increased by 25%. Applying the highest electric field of 55.55 in 1000 microseconds caused 14% ascorbic acid degradation compared to fresh samples. With increasing pulsed electric fields, the cloudy index of the sample and browning index have increased. The use of high intensity pulsed electric field increased the degradation of PME enzyme and the cloudy index and reduced lightness compared to the fresh sample. Preservation of sensory properties of key lime juice developed with PEF during shelf life showed that the non-thermal pulsed electric field method can act as a promising approach in products with high acidity and enzyme degradation. [ABSTRACT FROM AUTHOR]

Strawberries have a very short shelf-life due to their high sensitivity to fungal agents. The use of chemical antifungal compounds to increase the shelf life of this fruit has raised many concerns. For this reason, it is necessary to use safe methods to control spoilage and maintain the quality of strawberry fruit during storage. In this study, the effect of coating with Persian gum containing vanillin on the shelf life of strawberry fruit was evaluated. The levels of gum used in the preparation of the coating solution were 3%, 3.75 and 4% (w / v) and vanillin was added to the coating solution at three levels of 5, 6 and 7 mM. The studied characteristics included weight loss percentage, general acceptance, acidity, soluble solids, breakdown percentage, anthocyanin content, texture analysis and vitamin C content. The results showed an improvement in the appearance of coated fruits compared to control samples and also a significant reduction in the percentage of spoilage and weight loss in coated samples compared to the control. According to the results, the titratable acidity and texture firmness in the treated fruits improved compared to the control samples. Anthocyanin content and vitamin C content in the coated samples decreased but the rate of decrease was much slower compared to the control samples. Overall acceptance in the coated samples decreased slightly compared to the control sample. Finally, the best formulation was determined to contain 3.96% (W/V) of Persian gum, 0.857 mM vanillin and 2% (V/V) of glycerol. [ABSTRACT FROM AUTHOR]

Grape is one of the most important fruits in the world and despite being nonclimacteric, itsquality decreased rapidly. The main goal of post-harvest technology is to reduce losses during the post-harvest period. Different methods have been proposed to increase the shelf-life of fruits and vegetables, mainly including the use of chemical preservatives that have problems and limitations. Nowadays, demandforusing natural compounds including active edible coatings for keeping fruits quality has increased. This study was conducted to investigate the effect of maltodextrin edible coating containing different concentrations of chitosan and olive leaf extract on shelf-life and qualityattributes (including total soluble solids, fruit juice pH and acidity, flavor index, total phenolic compounds, vitamin C and organoleptic properties) of black grape fruit (Rashehvariety) during 90 days of storage period. Results showed that using maltodextrin coating containing chitosan and olive leaf extract reduced weight loss and prevented the degradation of phenolic compounds and vitamin C of samples during storage period. Increasing storage time resulted in a decrease in the amount of acidity and increased pH of samples, while increasing chitosan concentration and olive leaf extract increased the maintains of organic acids and decreased the pH of grape samples. The amount of total soluble solids in grape samples increased with increasing storage time. Results showed that the use of maltodextrin coating containing chitosan and olive leaf extract maintained the quality and reduced the degradation of the sensory properties of grape fruit during storage period.The best conditions for storing grape fruit include maltodextrin coating containing 2% chitosan and 0.75% olive leaf extract. At these conditions, storage time is about two months (57.30 days) and in this period, grape fruit has the minimum weight loss, but vitamin C and total acceptabilityare maximum, the desirabilityof these optimum conditions is 0.703. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of GABA postharvest treatment on storage life and nutritional quality of fresh cut button mushroom, mushrooms treatment with five concentrations (0, 0.01, 0.1, 1 and 10 mM) of GABA done, and stored in the refrigerator for 15 days at a temperature of 4 °C and a relative humidity of 90±5 %, and the mushroom were sampled on days 0, 5, 10 and 15. The results showed that the concentration of 1 mM GABA had a greater effect on reducing the browning index of fresh cut button mushrooms than other concentrations of GABA. Reduction of electrolyte leakage and accumulation of malondialdehyde was observed in fresh cut mushrooms treated with a concentration of 1 mM GABA, which reduced weight loss in these mushrooms. High activity of phenylalanine ammonialyase enzyme in mushroom treated with 1 mM GABA increased the content of phenolic compounds which was associated with decreased activity of polyphenol oxidase enzyme. An increase in antioxidant capacity was observed in 1 mM GABA-treated mushrooms, which was accompanied by a significant increase in ascorbic acid accumulation in these mushrooms. Therefore, GABA as a safe and effective method can be used to increase the shelf life of fresh cut button mushrooms. [ABSTRACT FROM AUTHOR]

Lecithin -based liposomes were studied as carriers of vitamins E and C to enrich lentil/buckwheat-based fermented beverages. Liposomes prepared by hydration method. Particle size and shape were analyzed by light scattering and scanning electron microscopy. The percentage of encapsulation efficiency of vitamins E and C was determined by HPLC method. The encapsulation efficiency of vitamin E and C nanoliposome's was 88.5% and 50%, respectively. The average volume diameter of vitamin C nanoliposomes was smaller than the average volume diameter of vitamin E nanoliposomes. The results showed that the produced liposomes are stable nanoliposomes with small size, low Polydispersity index and single-mode with high negative surface charge. Electron Microscopy Images showed nanometer-sized spherical nanoliposomes. Vitamin E nanoliposomes had higher turbidity compared to vitamin C nanoliposomes. Adding vitamin E and C nanoliposomes to the fermented beverage not only had no negative effect on the chemical composition and sensory acceptance of the drink, but also increased the total phenolic contents and antioxidant properties. [ABSTRACT FROM AUTHOR]

One of the most important problems in the field of cultivation and production of garden products, especially oranges, is the irrigation of the plant and its amount. Iran has many challenges in growing and producing orange fruit due to its diverse climate and being located in a dry region. Based on, in the present study, the effect of water stress and storage time of the product in cold storage (fruits of Thomson Novell cultivar after harvest in cold storage at 5 ° C and 85% humidity for 90 days and Valencia oranges at 20 ° C for Stored for 30 days) on chemical properties (antioxidant activity, ascorbic acid content), physical (weight, width, length, volume, volume, weight and weight of the extract), color characteristics and sensory properties were evaluated. The physical changes of Thomson and Valencia oranges in the samples without water stress on the first day were not significantly different, although minor reduction in storage time. According to the results, the highest weight loss, extract weight, antioxidant, ascorbic acid and volume of orange varieties during storage were in samples under dehydration stress. The color components include brightness, a * and b * decreased in Thomson orange samples under water stress and during storage, but the Valencia orange but did not significant difference was observed. Sensory properties of bad taste and bitterness were higher in oranges under water stress and scored lower in terms of sensory evaluators. [ABSTRACT FROM AUTHOR]

The post -harvest techniques of medicinal plants such as drying, is very important in their production cycle. The present study was carried out to evaluate the effect of different drying methods on some phytochemical traits of Chuchak in the spring of 2020 based on the completely randomized design with three replications. The chuchak samples were collected in the vegetative stage from the gardens of Noor city, Iran. The drying treatments were shade -drying at room temperature (25 ±3°C), sun -drying, oven -drying (45, 55 and 65°C), vacuum oven -drying (45, 55 and 65°C), microwave -drying (200, 500 and 800 watts), and fresh samples. The studied traits were moisture content based on fresh and dry weight, drying time and speed, ascorbic acid content, protein content, total carbohydrate content, total phenol and flavonoid content and antioxidant activity. The results of the variance analysis showed the significant effect of drying methods on all studied properties of the samples (P ≤0.01). The mean comparison showed that the minimum drying time and the maximum speed drying were related to the microwave (800watts). The highest amount of ascorbic acid (385.72 µg/mg), protein (19.72%), total phenol (47.19 mg GA per 1 g dry matter), total flavonoids (50.96 mg quercetin per 1 g dry matter) as well as antioxidant activity (76.02%) was observed in the fresh plant and then in the oven -drying (55°C). [ABSTRACT FROM AUTHOR]

In this study, the effective moisture diffusivity and activation energy of apples with %84 w.b moisture during one - and two -stage drying were investigated. The blanching was done at 5 minutes in 1% ascorbic acid to browning inhibition. The un -blanched samples were controlled. Drying ran with four methods. Two methods consist of oven drying through one stage at 50, 60, and 70 ℃, two -stage at (50 -60, 50 -70, 60 - 70 ℃), and microwave drying with one stage (90, 180, and 360 W) and two -stage in (90 -180, 90 -360, 180 -360 W) treatments. the equilibrium moisture was 20%. In two -stage drying, when the moisture of samples reached %50 on initial moisture, the temperature or power changed to next. The effective moisture diffusivity and activation energy were calculated as results. Results show when the microwave power increases, the drying rate and thus the effective moisture diffusivity increase. The moisture removal is better in two -stage drying. The blanching has a lower effect on effective moisture diffusivity in hot air drying. The temperature had no significant effect on effective moisture diffusivity during two -stage drying. During drying with microwave, increasing power reduced the needed energy for removing the moisture from the apple surface which shows the activation energy. Without considering the blanching process in two -stage dried samples, the best power of microwave was 90 W and then 360 W. in this power, the low initial energy for drying and low activation energy are the important benefits of drying. Blanching can reduce the amount of needed energy for starting the evaporation of water. In two-stage drying, increasing the power leads to decreasing the activation energy, without considering the blanching process. Finally, drying of samples with oven and microwave in two stages caused better emission of moisture and reduction of the required energy for starting moisture evaporation in apple sheets. [ABSTRACT FROM AUTHOR]

The present study was carried out to determine the effects of UV irradiation on postharvest and quality of desert truffle. in order to increase the shelf life of desert truffles, truffles were irradiated with UV -C (2.2 mW cm - 1 ) at three different times, (control), 10 and 20 minutes and also storage in 7%, 10%, 13% 16% (w/w) NaCl and 5% vinegar solution (w/w). After applying the desired treatments, truffles were stored at 4 ° C for 160 days and sampling was performed at 40 - day intervals. Weight loss percentage, tissue firmness, phenolic compounds, vitamin C content and microbial load were evaluated.Tissue firmness was higher at the truffles that were exposed to radiation for 10 minutes than other treatments. Also, radiation had a significant effect on preventing weight loss of truffles. The lowest weight loss was related to 10 minutes of radiation treatment and also, the highest amount of weight loss was related to control treatment. Radiation at higher doses does not further improve tissue quality parameters and causes skin necrosis and damage to truffle tissue. Evaluation of truffles phenolic compounds such as caffeic acid, ferulic acid, vanillic acid, coumaric acid, cinnamic acid and catechin was measured by HPLC. Evaluation shows that radiation had a significant effect on the increase of phenolic compounds in truffles, however the amount of these compounds decreased significantly over time. Irradiation also had a significant effect on reducing the microbial load and irradiated truffle had the lowest amount of microbial growth. However, the most effective treatment to maintain tissue quality characteristics and prevent weight loss and inhibit bacterial spoilage, UV -C (10 minutes) and immersion in vinegar and Storage at 4 ° C compared to other treatments was expressed during 160 days of storage. [ABSTRACT FROM AUTHOR]

Tomatoes are widely produced and consumed worldwide due to their high nutritional value as well as unique sensory properties. The high perishability and low shelf life of tomatoes necessitate the use of novel processing methods. In this research, the possibility of using vacuum frying technology in the processing of tomato slices, the effect of process variables (processing time, oil temperature and pressure inside the chamber) on some quality characteristics of the final product (moisture and fat content, shrinkage, ascorbic acid, color and texture brittleness) as well as determining the optimal processing conditions in a vacuum lab-scale frying systemwith precise control of process conditions were investigated. Initially, by performing pre-tests, the range of variables of the study included frying temperature (115-135°C), pressure inside the chamber (260-340 mbar) and process time (15-25 minutes) was determined. The results of study showed that the process temperature has significant effects (P≤0.05) on the moisture content, shrinkage, fat content, ascorbic acid content and texture brittleness, so that with increasing temperature, the moisture content and ascorbic acid content decrease and shrinkage, fat content and tissue brittleness increase. Processing time showed significant effects (P≤0.05) on the moisture content, shrinkage, fat content and texture brittleness, so that with increasing process time, the moisture content decreased and shrinkage, the fat content and texture brittleness, increased. Operating pressure had significant effects only on shrinkage and total color change characteristics (P≤0.05). Increasing the operating pressure led to a reduction in shrinkage and an increase in total color changes.Optimum vacuum frying conditions of tomato slices were a temperature of 135°C, time of 21.92 minutes and pressure of 260 mbar, under these conditionswere the moisture content, shrinkage, fat content, amount of ascorbic acid, total color changesand the breaking force were45.93%, 70.54%, 34.64%, 2.92 mg/100 mL, 64.86 and 2.58N, respectively. [ABSTRACT FROM AUTHOR]

In this study, cantalupe seed protein (Cucumis melo var cantalupensis) were used to obtain bioactive peptides with maximum antioxidant power (DPPH radical scavenging activity and reducing power for alkalase treatment,. For this purpose, in this study, the response surface methodology and central composite design with different levels of independent variables of enzyme to substrate ratio (E / S) 0.25%-3.25%, hydrolysis time 30-210 min, temperature 30C°-55 °C for alkalase enzyme. Optimal condition treatment obtained as enzyme to substrate ratio (E / S) 0.86, hydrolysis time 173.51 min and temperature 49.93 °C and adjasted- R2 for DPPH radical scavenging activity were 0.80 and 0.58, respectively, and for Fe2+ reducing power were 0.96 and 0.91 (alkalase treatment), respectively., indicating that the fitted model had a relatively good description of the data distribution. Antioxidant tests were performed using different concentrations of 50-200 ppm of the optimal treatment, and the results showed a positive effect of concentration on antioxidant properties. In all samples, hydrolyzed protein with alkalase showed higher antioxidant properties compared to unhydrolyzed protein, but was lower than the antioxidant activity of ascorbic acid as a positive control. The antioxidant properties of bioactive peptides make it possible to use them as a natural alternative to common antioxidant compounds in the food industry. [ABSTRACT FROM AUTHOR]

One of the reasons of the bakery products poor quality and quality defection in the country is the low quality and the impropriety of wheat. Regarding the uncontrollability of so many effective factors in wheat quality. Using of improving agents in wheat flour has been highly considered. In this study, the effect of tow improving agents, ascorbic acid in three levels (20, 40, 60 ppm) and α-amylase enzyme in three levels (25, 50 and 75 ppm) over dough was investigated. Rheological tests results showed that increasing level of ascorbic acid from 20 ppm to 60 ppm is effective in dough stability time and dough developing time increment, reduction in dough softening degree, increasing elasticity, improving gluten structure and increasing the usage level of α-amylase enzyme from 25 ppm to 75 ppm is effective in the collapse of polymeric structure of starch, dough softening, stability, developing time and reduction elasticity characteristics. In simultaneous use of additives in constant amount of α-amylase enzyme, increase of ascorbic acid from 20ppm to 60ppm causes rheological individually betterness. Dough stability time, developing time and dough elasticity as well. This effect in constant amount of ascorbic acid shows a diverse relationship specially with high amount of added α-amylase (50 and 75 ppm). Generally, in addition to ascorbic acid containing treatment on its own using of α-amylase enzyme in 50 ppm level with 60 ppm ascorbic acid in improving the rheological and quality specialty of dough is suggested. [ABSTRACT FROM AUTHOR]

Ultraviolet radiation is one of the environmentally friendly methods that was used in the present study to process lemon juice. The designed UV system had five UVC lamps and irradiation was performed based on the distance of the lamps (10, 20, and 30 cm) from the fluid layer and the circulation time (10, 20, and 30 minutes) of lemon juice in the system. Non-irradiated sample was also considered as a control treatment. The control and irradiated samples were filled in dark polyethylene bottles and stored at ambient temperature for 90 days. Immediately after irradiation and during the storage period, parameters such as pH, titratable acidity, total soluble solids, ascorbic acid content, color indices (L*, a*, and b*) and browning index, as well as sensory attributes (color, taste, aroma, and overall acceptance) were evaluated. The pH, acidity, and total soluble solids did not show a definite trend. The results showed that among the color indices, L* decreased significantly, but a* and b* increased significantly during the storage period. The rate of color changes in irradiated samples from a distance of 10 cm was higher than other treatments. Irradiation also significantly reduced the ascorbic acid content of irradiated samples from a distance of 10 cm compared to other samples and control. However, the browning of irradiated samples from 10 cm distance was significantly less than that of irradiated samples from 20 and 30 cm distance. The score of the panelists indicated that irradiation and storage time altered the quality characteristics of lemon juice. The panelists' scores showed more acceptance of irradiated samples from 20 and 30 cm distance compared to irradiated samples from 10 cm distance. In general, the designed system in this study is not recommended for lemon juice processing due to the destructive effect of UV-C radiation on the content of ascorbic acid. [ABSTRACT FROM AUTHOR]

Cornelean cherry is a very perishable fruit that requires proper postharvest management to reduce losses. This study was aimed to increase the postharvest life and marketability of the product using postharvest calcium chloride treatments. The present study was conducted in a factorial experiment based on a completely randomized design with three replications. Factors included 3 immersion calcium chloride treatments (0, 60 and 80 mM), 4 storage times (0, 10, 20 and 30 days) and two cornelean cherry genotypes. Fruit samples were harvested at maturity (more than 90% of red skin) and immersion treatments were applied on them. During and after the experiment, different physicochemical traits of fruits were studied. The results showed that KKP2 genotype had lower mean firmness and sugar content and higher weight loss percentage than Hir genotype. The results showed that the two genotypes did not show significant differences in terms of pH and titratable acidity. Firmness, titratable acid, ascorbic acid, anthocyanin and phenol decreased over time. Among immersion treatments, the highest and lowest firmness, titratable acid and ascorbic acid belonged to 60 mM calcium and control (distilled water), respectively. The difference between 60 and 80 mM calcium chloride treatments was not significant. [ABSTRACT FROM AUTHOR]

In this research, in order to optimize the extraction process of Ethanolic extract of barberry fruit, the increase and optimization of the conditions for the extraction of anthocyanin's and bioactive compounds by means of intermittent electric field pre-treatment from three levels of electric field intensity (0.5, 1.75 and 3 kV / cm) and 3 levels of number of pulses (15, 30 and 45); then with ethanol solvent was used to extract their extracts and the amount of flavonoids, total anthocyanin, DPPH, total phenolic compounds, iron regeneration capacity, vitamin C and acidity compared to control (no treatment) Was studied. The results showed that the total phenol content of the extract decreased by increasing the number of pulses and reducing the intensity of the pulsed electric field applied to the sample. The increase in the electric field strength and the number of pulses initially increased the flavonoid content, DPPH and iron ion recovery capacity, but with the increase of these variables, these three parameters decreased. Also, with increasing of these parameters, the anthocyanin level and vitamin C content increased. The acidity of the sample was reduced and then increased by increasing the electric field strength and applied pulse number. Regarding the results of the process optimization, it can be concluded that the electrical field intensity of 2.003 kV / cm and applying 29 pulses can increases the antioxidant properties of the produced product compared with the control sample. [ABSTRACT FROM AUTHOR]

Drying is one of the oldest methods of food preservation, which usually have adverse effect on the physicochemical properties and nutritional value of the final product too. Today, the demand for application of rapid drying methods such as using microwave and infrared beams has increased to prevent or reduce undesirable changes in foods. In this study, the effect of infrared drying process condition (drying temperature and time) on weight loss, vitamin C and color properties of Shahsavar Yazdi pomegranate arils were investigated and optimized by response surface method. The results showed that the amount of weight loss and L* value of pomegranate samples, increased with increasing drying time and temperature, while the amount of vitamin C decreased. Drying temperature had a greater effect on weight loss and vitamin C changes compared to drying time; however, variation of L* value under the influence of infrared drying time are more severe than the drying temperature. The amount of a* and b* value increased with increasing drying temperature while decreased with increasing infrared drying time. The best conditions for infrared drying of pomegranate arils are using drying temprature of 55 °C for 600 minutes and by applying the optimal conditions, the amount of weight loss, vitamin C and the total color difference (ΔE) of the produced pomegranate arils are equal to 69.5, 12.89 and 5.79 respectively. The results of the optimal conditions validation test showed that by applying the obtained conditions from the optimization process, the quality attributes of pomegranate such as weight loss, amount of vitamin C and the total color difference (ΔE) of the produced samples were 70, 12.45 and 7.75 respectively, which are very similar to the obtained results from the optimal conditions predicted by the response surface method. [ABSTRACT FROM AUTHOR]

Oxalic acid (OA), as a natural antioxidant, delays the ripening and senescence of fruits. In this research, the effect of different concentration of OA (0, 2, 4, 6, and 8 mM) investigated on storage life and postharvest quality of loquat fruit at 5°C and 90±5% relative humidity for 28 days. Traits such as browning index, biochemical and qualitative characteristics and activity of polyphenol oxidase (PPO) and peroxidase (POD) enzymes of fruit at harvest (0), 7, 14, 21 and 28 days after storage were analyzed. With increasing storage time, the level of browning index, total soluble solids (TSS), ratio of TSS/titratable acidity (TA) and the activity of PPO and POD enzymes increased in all treatments, while firmness, ascorbic acid, total phenol and flavonoids content and antioxidant activity decreased (p˂0.05). OA application significantly reduced the level of browning index and the activity of enzymes responsible for tissue browning (PPO and POD) compared to control (p˂0.05). At the end of storage, fruits treated with different concentration of OA had a more firmness tissue and higher level of ascorbic acid, total phenol and flavonoids content and antioxidant activity in comparison to the control fruits (p˂0.05). Overall, OA application effectively reduced fruit softening and browning index with diminished the activity of PPO and POD enzymes during cold storage. [ABSTRACT FROM AUTHOR]

Pistachio is one of the most popular nuts in the world because of its taste and nutritional properties. Mostly, its consumed dry in harvest period. Major factors limiting for shelf life of pistachios are browning and water accumulation. In this study, the effects of citric acid (1, 1.5 and 2%) and ascorbic acid (15, 25 and 35 ppm) and two types of plastic packs (polyethylene and polystyrene) on storage life (days 0, 25 and 45), Ahmad aghaie pistachio was studied. According to panelists, the use of acid treatments for 25 day of storage was able to maintain the appearance and taste characteristics of pistachio and since then there was no significant difference between treatment and the control sample. Pistachios treated with 15 ppm ascorbic acid in polystyrene pack were more favorable in appearance and browning than polyethylene pack. The maximum of phenol was related to ascorbic acid treatments (15 ppm) in polyethylene pack. Anthocyanin and chlorophyll amount decreased during storage, but carotenoids first increased and then decreased. Pistachio pigments such as chlorophyll, anthocyanin and carotenoids were preserved in polyethylene packages than polystyrene. Citric acid treatment (1.5%) had the maximum percentage of fat. Overall, the polyethylene pack and ascorbic acid 15 and 25 ppm and citric acid 1.5% concentration maintained the qualitative and quantitative properties of pistachio. [ABSTRACT FROM AUTHOR]

As one of the most important nuts, hazelnut (Corylus avellana L. ) contain a valuable set of antioxidants and nutrients. The quality of hazelnut kernel was strongly affected by kernel compounds. The antioxidant capacity and biochemical compounds depends more on the cultivar, climatic conditions and the interaction between climatic conditions and genotypes. The present study was conducted to determine the quality properties including vitamin C, antioxidant activity, total phenol, flavonoid and mineral element in 11 cultivars and genotypes included seven imported cultivars (Ronde dupimont, Negreta, Segorbe, Sivri, Morfineski, Fertile decotard and Sochi), and four local Iranian genotypes (Eshkevar1, Eshkevar2, Eshkevar3 and Eshkevar 4) in the Rudsar Eshkevarat region in 2017. Analysis of variance results were showed that there was significant difference (P≤0. 01) among examined cultivars for all characters and showed high genetic variation in all of the studied cultivars. Correlation analysis showed the existence of significant positive and negative correlation among some important traits. According to the cluster analysis dendrogram performed by "Ward" method, cultivar and genotypes of hazelnut in Euclidian distance 27 were classified into four clusters. [ABSTRACT FROM AUTHOR]

In recent years there has been extensive research into the use of edible coatings in food packaging. Today, the use of edible coatings has increased due to consumers' desire to purchase products that maintain their freshness. In this research, edible coating based on different percentages of Spirulina platensis (0.5-1.5%) with constant percentages of gelatin powder (2%), chitosan powder (1%), and glycerol as lubricants was used. Physicochemical properties such as moisture content, pH, Acidity, color, total phenol, nutritional properties such as protein content, iron content and ascorbic acid content, sensory evaluation and microbial characteristics of control and other treatments were evaluated at days 0, 7 and 14 after production. The results of chemical tests showed the moisture content, acidity, phenol level were increased with increasing of Spriulina platencis in different treatments. The results of colorimetric analysis also showed that by increasing the percentage of spirulina the transparency of treatments decreased. The results of nutritional evaluation showed that there was a significant difference in protein, iron and ascorbic acid levels with increasing of Spirulina platensis (p <0.05). Increasing the amount of spirulina platensis was effective on the microbial growth as well as the taste and color of the treatments, which was diagnosed by sensory evaluation. [ABSTRACT FROM AUTHOR]

Drying due to the adverse physical and chemical changes is one of the most difficult processes in the food industry, especially to produce garlic powder. In this study, in order to avoid the Maillard reaction, garlics were pretreated by 0.5% sodium metabisulfite, 10% NaCl and citric acid (up to pH = 4) solutions. For this purpose, first, fresh garlic, after preparation according to the usual industrial method, was immersed in the pretreatment solution for 2 minutes at room temperature. The treated garlic was dried using cabinet method at 80 °C and 90 °C to achieve 5.2% water content, and then stored for 60 days at room temperature to evaluation of some quality characteristics including moisture content, vitamin C content, browning level, flavonoid content and pH. Based on the obtained results, moisture content did not change significantly in all treatments during storage. Control sample (without pretreatment) had had the highest off color and browning. Flavonoid and vitamin C contents were reduced in pretreated samples due to their solubility in water. Generally, based on the obtained results, garlic powder produced by pretreatments had lighter color than control sample which could increase their market acceptance and pretreatment with salt had highest effect in the production of garlic powder with a suitable color. [ABSTRACT FROM AUTHOR]

Ostrich fillets is highly edible and one of most healthy and the least fat red meat samples. Due to carcass contamination along the slaughter chain, it becomes corrupted by the growth of meat microorganisms during storage. Being biodegradable, edible and efficient have caused edible films to be widely investigated and used as a good replacement for synthetic materials in packaging of food products. In this study a gelatin/frankincense (G/F) bilayer film was produced from gelatin and frankincense monolayers using the casting method in two phases. This research investigated antimicrobial activity of various concentrations of acid ascorbic (0, 1% and 2%) and Hyssopus officinalis oil (0, 0.75% and 1.5%) in edible bilayer gelatin/frankincense against Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas aeroginosa. on the other hand, effect of edible film was evaluated on microbial and chemical properties of ostrich meat for 12 day at refrigerator temperature. Diameter of inhibition zone showed that Staphylococcus aureus and Pseudomonas aeroginosa were most sensitive and resistant bacteria respectively. Compared with control sample, two treatments (G/F+2%AA+0.75%HO and G/F+2%AA+1.5%HO) decreased total viable count, psychrophilic and lactic acid bacteria significantly (p<0.05). The result also showed with addition Hyssop oil and ascorbic acid, pH and peroxide values notably reduced compared with pure edible film (without oil and acid)( (p<0.05). The gelatin/frankincense films enriched with essential oil and vitamin C delayed tissue breakdown, and increases the pH by reducing the bacterial growth. Therefore, antimicrobial edible film containing Hyssop oil and vitamin C as an economical and biodegradable coating has a good potential for increasing the shelf-life of ostrich meat at the refrigerator (4Ċ) temperature. [ABSTRACT FROM AUTHOR]

Oxidative stress factors are known to causes some metabolic disorders diseases. Therefore, preventing, or at least decreasing the amount of these factors may have a positive impact on prevention or improvement of the metabolic diseases. Recently, the herbal medicines are more considered due to more effectiveness. The present study was designed to evaluate anti-oxidant effect of sumac powder (Rhus coriaria L.).In the present study, special parts of the sumac plant, dried at room temperature and powdered using laboratory mill. All samples were solubilized in methanol, and four concentrations (12.5, 25, 40 ،50 μ/ml) were prepared and the antioxidant activity of sumac powder measured by DPPH at a wavelength of 517 nm. Finally, the IC50 of all samples and the standard were calculated and compared with standard.The methanol extracts of all sumac doses showed dose-dependent potent antioxidant activity. The results indicated that brown sumac powder (IC50 = 14/912) has the higher antioxidant activity compared to red sumac powder (IC50 = 27/385), which was lower than vitamin C (IC50 = 6/708). Brown sumac powder has a stronger antioxidant effect than red sumac powder, which can be effective in improving the antioxidant defense of the body, so we advise to consume brown sumac. [ABSTRACT FROM AUTHOR]

In the present study, the influence of drying temperature on energy consumption and qualitative characteristics of onion including rehydration capacity, vitamin C content and total phenolic content (TPC) was investigated. Onion slices with 3 mm thickness was dried in a hot air dryer at temperatures 0f 40‒70 °C. Specific energy consumption and energy efficiency were significantly (P < 0.05) improved by increasing temperature and obtained to be in the range of 35.83‒59.33 MJ/kg and 4.01‒6.52%, respectively. Increasing air temperature resulted in significant (p < 0.05) improvement in energy consumption indices. Rehydration capacity in the dried onion samples varied from 4.01% (at drying temperature of 40 °C) to 6.52 (at drying temperature of 70 °C). Vitamin C content in fresh samples was 50.19, and in dried samples varied from 14.92 to 21.38 mg/100 g dry matter. TPC was measured using Foline–Ciocalteu reagent and found that the TPC in fresh onions (389.6 mg GAE/100 dry matter) was significantly (p < 0.05) decreased in the dried samples (212.3‒295.8 mg GAE/100 dry matter). Based on the obtained results, drying of the onions at higher temperatures led to more deterioration in vitamin C content and the TPC. [ABSTRACT FROM AUTHOR]

The storage of fish in the refrigerator reduces the speed of enzymatic and chemical activities and the activity of microorganisms, but due to the inability of the refrigerator temperature to reduce the temperature of the fish, adverse changes such as oxidation and fatty hydrolysis will be done. This study carried out on the effects of vitamins C, AD3E, and mixed vitamin C and AD3E on the shelf life of Carangoides fulvoguttatus fish fillets during three-months period in a refrigerator at 6 °C. For this purpose, a fish piece with a weight of 2381 gr was provided from Behbahan city market and was transferred with ice cover to the Fisheries Laboratory of Khatam-Al-Anbia University of Technology in Behbahan. After separating the scales, weaning and scrubbing, the fillets were separated and stored in a 90 gr packages in refrigerator at 6 °C for 3 months. Some fish samples were also tested freshly. The experiments included measurements of fat, protein, ash, moisture, energy and acidity. Based on the results, the highest percentage of protein belonged to the sample containing vitamin C. The highest fat percentage was observed in control treatment with 12.19% and then in treatment AD3E with 9.9%. The moisture content of the experimental treatments was also significantly higher than the control sample. Therefore, it can be concluded that vitamin C, as well as AD3E solution, preserved the nutritional value of fish fillet during the storage period in the refrigerator [ABSTRACT FROM AUTHOR]

In this research, physicochemical and antioxidant properties of two varieties of lemon (Cook Eureka and Khoushehi) were evaluated during two years by sampling from October 17 to November 16, every 10 days (four times) from trees and at the end of shelf life period. The results showed, generally, the size and volume of fruit of Cook Eureka was large and Khoushehi lemon was small. The fruit weight and juice percentage in Cook Eureka did not change significantly (p<0.05) during harvesting time and shelf life. The TSS/TA ratio also increased during ripening and shelf life, with the exception of the Khoushehi fruits which harvested on November 16. Although the technology index in Cook Eureka was not significantly change during harvesting times, but the peel thickness of Khoushehi fruits decreased during shelf life. In general, the values of L*, a* and b* color indices in both varieties and experiment were high from first to last harvest times. Also, amount of Chroma and CCI showed an increase pattern during shelf life. Fruits picked at the last harvest (Nov. 16), which had the highest amount of vitamin C (28.31 mg/100gFW), also had the highest vitamin C levels at the end of shelf life (42.64 mg/100gFW). Totally, the total phenol and antioxidant content of fruit were increased during shelf life period in both varieties. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Antimicrobial packaging is one of the most important applications of active packaging. The purpose of this study was to investigate the effect of antimicrobial packaging on the quality of strawberry fruit cv. Camarosa The experiment was conducted as factorial in a completely randomized design with four types of fruit packaging control with no inoculation and inoculation of fungi, 12 and 24 μl of essential oil /ml air and the second factor was sampling time (harvest time, 4, 8 and 12 days). During the experiment, traits qualitative and biochemical properties were investigated. The results showed that with increasing storage time in all treatments, decay percentage, weight loss, total anthocyanin, total phenol and flavonoid increased, while the amount of vitamin C and antioxidant capacity decreased. The amount of vitamin C, flavonoids and antioxidant capacity in fruits treated with peppermint essential oil were significantly higher than those of the control group. The microbial populations during the storage period was decreased in the treatment of essential oils. Totally, It seems that The concentration of 24 μl / ml peppermint essential oil loaded with microselle foam with slow release could reduce the percentage of fruit decay and microbial populations and maintain the qualitative and biochemical properties of strawberry fruit during cold storage. Considering that the essential oil of peppermint is very effective on the growth of Botrytis cinerea due to the presence of dominant components such as menthol and menthol at relatively low concentrations, so using this essential oil instead of artificial preservatives, It looks like something useful and effective. [ABSTRACT FROM AUTHOR]

A factorial experiment with 3 factor based on RCD was considered in order to evaluate effects of MAP and propolis on postharvest quality of spinach (Spinacia oleraceae cv. Varamin 88). The first factor was storage time in 4 levels of 7, 14, 21 and 28 days; second factor was gas mixture in 3 levels of air composition, O2 15% + CO2 5% and O2 5% + CO2 15%; and third factor was propolis on 3 levels of zero, 5% and 10%. The ANOVA results showed that all characters except chroma and chlorophyll b had significant differences at levels 1 and 5%. The amount of the acid Ascorbic was 275.1 mg/100gfw before storage and after a week this value modified to 171.1 mg/100gfw and after 14 days reached to 141 mg/100gfw. Using of propolis had statically significant effect in probability levels of 1 and 5% on hue angel, TSS, pH, acid, acid ascorbic, weight loss percent, and infection percent. Infection percent severely reduced affected by the use of propolis. The main effect of MAP treatment had significant influence on color indices, appearance quality, acid ascorbic content, weight loss and infection percents. Triple interaction of treatments had significant effect on ascorbic acid content at 5% level. Based on the obtained results use of 10% propolis and O2 5% + CO2 15% was the best treatment to increase the shelf life of spinach. [ABSTRACT FROM AUTHOR]