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This research was mainly devoted to evaluating the drying kinetics of mint leaves in a newly introduced solar dryer. In order to assess the drying kinetics of mint leaves, nine drying temperature levels (with the average value of: 41.3, 42.2, 44.1, 45.9, 47, 48.2, 50, 51.5, and 53.9°C and a corresponded drying time of 255, 255, 195, 180, 180, 180, 165, 165, and 150 min, respectively) were used. In addition, the corresponded values for the average drying rate levels were obtained as 2.19, 2.33, 2.96, 3.21, 3.35, 3.44, 3.51, 3.57, and 3.84% dry basis/min, respectively. Specific energy consumption of drying was calculated, which varied 5.5 to 8.6 MJ/kg of water removed. Also, 11 semiempirical models were applied to find the best‐fitted thin layer drying model, and an approximation of diffusion model has the highest correlation (R2 = 0.98, root mean square error = 0.041, k2 = 0.0017) with the experimental moisture ratio than the other models. Also, emitted carbon dioxide due to energy production from fossil fuel for usage in the electrical pump was calculated as 0.3 kg of CO2/kg of water removed. Hence, it can be concluded that the introduced solar drying technique is an eco‐friendly apparatus which was successfully used for the drying of mint leaves.Practical applicationApplication of solar for production of heating energy can cause to emit lower CO2, and consequently lower environmental pollution will occur. Hence, apparatuses with fossil fuel consumption can be replaced with this dryer. Also, due to lower air flow and temperature, this dryer can be used for drying of pharmaceutical plants such as mint leaves. Therefore, the introduced dryer has lower specific energy consumption and higher energy performance as a suitable dryer for industrial usages.

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Terminal velocity is an important factor, which is useful for designing different unit operations such as hydro transport and sorting of fruits. The current investigation is aimed to propose a new dimensionless model for terminal velocity of cantaloupe fruit. For this purpose, 30 fruits from three different varieties commonly known as Jana, Gerdabadi, and Shahabadi randomly were collected and, then, the physical properties, which may affect terminal velocity, were determined. On the basis of Buckingham theorem, six dimensionless groups were recognized and established to be used for dimensionless modeling of terminal velocity of cantaloupe fruit. Dependent pi‐term versus each independent pi‐term was drawn, and regression analysis was applied to draw the curves to produce linear equations, which can be used in the construction of the dimensionless model. In order to evaluate the obtained model, terminal velocity of six randomly selected fruits from each cantaloupe variety were measured and compared with the predicted terminal velocity values. A good agreement was achieved between the experimental and the predicted terminal velocities. Also, the coefficient of determination, mean bias error, and mean relative deviation of the comparison were calculated as 0.90, 7.9, and 10.35%, respectively. In this context, the obtained model can be used as an appropriate procedure for the prediction of terminal velocity of cantaloupe fruit as well as other similar fruits with good accuracy. Practical applications Development of a generalized dimensionless model describing terminal velocity of cantaloupe fruit as a function of various physical characteristics can be used in different units of food industries such as fruit compote preparation and juicer industries. It may also be used for the designation of sorting units and hydro transport of different fruits. In other words, the obtained model could be used to sketch unit operations, which involve some postharvesting activities for cantaloupe fruits.

(C5ICB) were used to analyze the data. The less C5ICB and C5 are, the more competitive balance is, and conversely. The C5ICB results showed that the leagues were ranked (ranging from most balance to least balance)

In the present work, the drying kinetics of osmo‐pretreated Aloe vera gel slices (AVGS) was investigated. AVGS with an initial moisture content of 98.29% (wet basis) were subjected to 5 hr of osmosis process (10% NaCl solution, at 40°C, NaCl solution to A. vera ratio = 5:1), prior to atmospheric thin layer drying at air temperatures of 55, 70, and 85°C and air volumetric air flow rates of 0.015, 0.036, and 0.054 m3/s for the duration of 160 min. Results showed the mean values of the moisture ratio in air temperatures of 55, 70, and 85°C were categorized into three levels (p < .01) of 0.551, 0.429, and 0.336, respectively, while the corresponding values for the osmo‐convective method were 0.561, 0.418, and 0.321, respectively. Similarly, the mean values of the moisture ratio in air flow rates of 0.015, 0.036, and 0.054 m3/s for the convective and osmo‐convective method assigned to different levels (p < .01) of 0.511, 0.417, 0.385 and 0.510, 0.416, 0.372, respectively. Superposition technique was utilized to propose a new model for each drying method. The predicted moisture ratios evaluated by the superposition technique were in a good agreement with experimental values of moisture ratio. Practical Applications In the current investigation, a superposition technique was utilized to propose a new model for two drying methods (osmo‐convective and convective). Subsequently, an equation describing the drying process for each method was derived. This technique while being a simple model, delivers high accuracy data for all influencing parameters in the drying process.