The energy and exergy analysis, drying characteristics and mathematical modeling of the thin-layer drying kinetics of white mulberry using microwave drying were investigated. Results indicated that values of exergy efficiency (33.63–57.08%) were higher than energy efficiency (31.85–55.56%). Specific energy consumption increased with increasing microwave power while improvement potential decreased. The specific energy consumption and improvement potential varied from 3.97 to 6.73 MJ/kg water and 0.71 to 2.97 MJ/kg water, respectively. Also, energy efficiency decreased with decrease in moisture content and microwave power level. The best exergy and energy aspect was obtained by drying at 100 W microwave power. Drying took place mainly in warming up, constant rate and falling rate periods. The Page model showed the best fit to experimental drying data. Effective diffusivity increased with decreasing moisture content and increasing microwave power. It varied from 1.06 × 10−8 to 3.45 × 10−8 m2/s, with an energy activation of 3.986 W/g.

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Effects of controlled atmosphere storage (CAS) and modified atmosphere packaging (MAP) in comparison with conventional cold storage on qualitative properties of green-mature harvested tomato were evaluated. Qualitative properties included firmness, redness value (a*), hue angle, Total Soluble Solids (TSS) content, Titratable Acidity (TA) and TSS/TA. Under CAS and MAP conditions, gas composition was 5 kPa O 2 and 3 kPa CO 2 . Results showed that the ability of CAS and MAP to retard the ripening process was more than cold storage. With regard to maintaining texture and colour, CAS treatment was the best and MAP was better than cold storage. Although amongst storage treatments, the maximum value of TSS was observed in cold storage, its decreasing trend in CAS was slower than that in cold storage. Additionally, MAP and especially CAS slowed down the diminishing trend of TA in tomatoes.

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The effects of gamma radiation treatment (50 and 100 Gy) on potato tubers irradiated at different days (10th, 30th and 50th) after harvest were studied during 5 months of storage at 10°C using Agria and Marfona varieties. A factorial experiment was done, based on a Randomized Complete Block Design with four replications. The 100 Gy radiation treatments on 10th and 30th days after harvest completely prevented sprouting at both varieties studied but on 50th day only Agria tubers not sprouted. This study indicated that early irradiation and absorbed radiation doses significantly decreased sprouting, percent weight loss and specific gravity of tubers. Reducing sugar content significantly increased by delay in irradiation and lower dose of radiation while non-reducing sugars did not decrease significantly by delay in irradiation and higher dose of radiation. The least increase in reducing sugars (10.2%) and most decrease in non-reducing sugar (-12.75%) were observed in tubers that irradiated on 10th day after harvest. The content of ascorbic acid was decreased by irradiation with higher dose. Although delay in irradiation caused less loss of ascorbic acid (8.5%) but showed greater metabolic changes as sprouting, weight loss, firmness, and sugars contents. Also, more increased delay in irradiation needed higher radiation doses for sprout inhibition.