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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 investigates the feasibility of achieving a modified rough rice air-drying with ultrasound intervention (US) set at 21 kHz frequency. The process was carried out using an ultrasound assisted convective dryer and analyzed in terms of drying time, energy consumption (EC), evaporation rate (ER), broken kernel (BK), water activity (aw), vitamin B3 (niacin), and total phenolic content (TPC). The lab-scale dryer was set to transmit energy at power levels of 30, 60, 90, 120, and 150 W in the air temperatures of 35, 40, 45, 50, and 55 °C and velocities of 0.2, 0.5, 0.8, 1.1, and 1.4 m/s for a thickness of 20 cm. The results showed that in-range drying parameters played a major role in response analysis, suggesting that ultrasound efficiency during convective drying heavily depends on the power, air temperature, and velocity levels. Ultrasound assistance significantly increased bed evaporation rate up to 38.93%. Subsequently, it caused a reasonable reduction in total drying time, EC, and BK percentage up to 27.92%, 25.98%, and 34.22%, respectively in the case of 35 °C, v = 0.8 m/s, and P = 90 W. Remarkable advances were attained in the ultrasound assisted drying domain in grain quality via acceptable decrease in niacin and TPC losses within shorter drying time. There was a significant linear trend in BK, niacin, and TPC values across the bed thickness, which all was increased by the ultrasound application. The highest nutrient retention and physical quality preservation belonged to the top layer, which was influenced by the ultrasound radiation by the highest degree.

Infrared assisted vacuum drying technology is a newly emerged strategy, which found its place in the food drying industry. Therefore, in this research, the effectiveness of near infrared (NIR) and ...

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...

In this work with a different technique we obtain upper bounds of the functional $\left|a_2a_4-a_3^2\right|$ for functions belonging to a comprehensive subclass of analytic bi-univalent functions, which is defined by subordinations in the open unit disk. Moreover, our results extend and improve some of the previously known ones.

This work aimed in modelling some physical and thermal properties of walnut kernel undergoing various drying techniques include microwave semi-industrial continuous drying (M-CD), microwave infrared-vacuum drying (M-IVD), and microwave infrared-fluidised bed drying methods. By using the verifications of experimental parameters, ten drying models for describing combined effects of independent variables were derived and the parameters of these models were determined by multiple regression analysis. In the case of the model, comprised of collective effects of drying independents, the Midilli model gave the best result in describing drying behaviour of walnut kernel in all experimental domains. Minimum values of shrinkage (6.53%) and colour change (5.54%) were obtained in the M-CD with the microwave power of 270 W, air temperature of 45 °C, and belt linear speed of 10.5 mm/s, however maximum shrinkage (14.65%) and colour change (18.28%) were related to the M-IVD with microwave power of 630 W, drying temperatu...

The purpose of the presented study was to describe the effects of various drying conditions on the drying behavior of zucchini slices as well as specifications of diffusivity, activation energy, shrinkage, and color. Zucchini samples, as the richest fount of macronutrient and micronutrient, were subjected to periodic microwave vacuum drying (at 450 W) at three levels of temperature (40, 50 and 60 °C), absolute pressure (20, 40 and 60 kPa) and exposure time (20–3, 30–4.5 and 40–6 s-min). An increase in the drying temperature and exposure time along with a decrease in absolute pressure caused a reduction in total drying time, however, greater heat damages and adversely texture and color effects were observed in this case. The effective moisture diffusivity of zucchini varied between 5.41×10−10 and 1.75×10−9, indicating that under circumstances of high temperature, long exposure time and low absolute pressure water was able to rapidly diffuse out of the tissue in the experimental domain. Lowering the absolute pressure of vacuum flask and increasing the exposure time led to the reduction in the activation energy of samples. The shrinkage coefficient was within the range of 79.91 to 84.92%. As such, the greatest total color difference was calculated between the color of raw and dried samples for those experiments with the largest increase in temperature, exposure time and a decrease in absolute pressure.

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.