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The aim of the present study was to evaluate the efficiency of sulfur dioxide release sheets on the basis of acetate cellulose film to control the growth of molds, especially botrytis cinerea, during the storage period of kiwifruit. For this purpose, the storage of kiwifruit inoculated with botrytis cinerea in the presence of one and dual sulfur dioxide releasing sheets (containing 30 and 50% metabisulfit salts, respectively) on the acetate cellulose bed was investigated. After 15 days of storage (9 days in cold store and 7 days in ambient temperature), the least bursting and crushing (4.5%) was obtained in the presence of single-stage sheets that were placed on the surface and bottom of the packages. Also, in the ninth day, mold was not observed in the 60% of packages in the presence of sulfur dioxide releasing sheets. On the 15th day, the amount of total sugar, acidity, firmness, residual sulfur, and soluble solids in packaged kiwis in the presence of two dual releasing sheets placed on the surface and bottom of packages were, respectively, 9.9 g/100 g, 1.09%, 4.75 N, 0.24 mg/g and 12.21%. In general, it can be said that sulfur dioxide releasing sheets have an effective function on cold storage in increasing the shelf life of fruits, especially fruits that are attacked by gray mold. [ABSTRACT FROM AUTHOR]

Microwave- assisted extraction is efficiency technic for extraction bioactive compounds and valuable in biological compounds that lead to accelerating the food heat processing, better extraction and quality, time decreasing and amount of solvent without decomposition of heat sensitive compounds that is applicable in both laboratory and industrial scales. The aim of this study, optimization of extraction was using response surface method and Face-center design, in order to investigate the effect of time (60-120 Sec), power (300-700 W) and ethanol percentage (40-80 %) on the yield of polyphenol,, and also the antioxidant activity and optimization of extraction process. The results showed that, model fitting was suitable. The phenolic content was decreased by increasing the ethanol concentration, significantly. Simultaneous increase of extraction time and power, resulted in significant increase of total phenolic, contents (P<0.05). Maximum yield of antioxidant compounds is achieved with extraction time of 120 sec, extraction power of 300 W and ethanol percentage of 80%. Under these conditions, the values have been assayed: 25.37(mg/100 g) for quercetin, 53.60% for DPPH free radical scavenging activity, extraction efficiency, 77.76%, and 47.43 (mg/kG) for total polyphenol and 416.79 (µm/g) for ferric ion reducing antioxidant power. As a result, Microwave assisted extraction method by two friendly environment solvent (water and ethanol) in different concentrations for extraction of bioactive compounds and antioxidant of onion by-products can used at a shorter extraction time and energy saving. [ABSTRACT FROM AUTHOR]

In this study, the changes in the color and some properties of carrot slices were investigated during hot air drying. The carrot slices first underwent an optimized osmotic pretreatment. The sucrose concentration of 60% and the dehydration time of 60 min were found to be as the optimum conditions of the osmotic dehydration. In hot air drying, temperature (60, 70 and 80°C) was taken into account as the independent variable and moisture content, shrinkage, rehydration ratio, total phenolic content, texture and sensory evaluation were considered as the dependent variables. The results revealed that the lowest reduction in total phenolic content was associated with 70°C and the effect of temperature on all of the responses was significant. With increasing temperature, shrinkage, rehydration ratio and texture increased but the moisture content decreased to (11 gr / gr). At the end, the optimum conditions were selected based on the maximum rehydration rate, phenolic compounds, total acceptance and minimum moisture content, shrinkage and stiffness of the texture were determined and the optimum temperature was 70 ° C. [ABSTRACT FROM AUTHOR]