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The objective of the present issue was to inquire the effect of ultrasound assisted convective drying on a thin layer of sunflower seeds. The process was carried out utilizing a hybrid chamber dryer, outfitted with an ultrasound generator with indirect transmission toward the material surface. Drying behavior was analyzed by drying time, effective moisture diffusivity (Deff), energy consumption (EC), water activity (aw), and total color change (ΔE). Independent variables of air temperature and ultrasound power determined the efficiency of sonication during drying. So that, ultrasound contributed to a noticeable increase in Deff up to 44.84%. Thereafter, a reasonable decrease was found in drying time, energy consumption, and total color change up to 40.85%, 32.95%, and 44.56%, respectively when collocating the variables of 35 °C, 3.5 m/s, and 2.4 W/g. The optimum drying condition in the pure convective drying domain was improved from 50.74 °C and 2 m/s to the condition of 40.64 °C, 2 m/s, and 3.932 W/g after sonication. In this point, significant reductions of 19.89% and 19.32% were observed in drying time and energy consumption. Optimization results confirmed that ultrasound intervention could provide an intensified and energy-efficient drying process, which generates sustainable and qualified dried seeds.

This study has examined the influence of ultrasonic-assisted hot air drying process on the dehydration behavior of in-bin rough rice (Oryza sativa) kernels. To this aim, the experimental drying kin...

Thin-layer drying kinetics of pistachio nuts were examined experimentally as a function of drying conditions in a fluidized bed dryer with microwave pretreatment. Four drying specifications of diffusivity, shrinkage, specific energy consumption and total color change were calculated and the effects of parameters were studied. Numerous experimentations were conducted at three levels of air temperature (40, 55, 70 °C), air velocity (1.2, 2.93, 4.01 m/s), and microwave power (270, 450, 630 W). The variation ranges of diffusivity, shrinkage, energy consumption and color change were recorded from 5.01×10–10 to 5.07×10–9 m2/s, from 26.95 % to 13.13 %, from 1.04 to 9.23 kWh and from 10.44 to 17.17, respectively. According to response surface methodology, optimum condition of drying process occurred at microwave power of 630, air temperature of 70 ˚C, and air velocity of 1.2 m/s. In this optimum point, the values of diffusivity, shrinkage, specific energy consumption and total color change were 4.865×10–9, 14.22 %, 2.164 kWh and 12.312, respectively.