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The finite element method was employed to model the simultaneous heat and mass transfer in cylindrical samples of banana during convective drying. The Arbitrary Lagrangian-Eulerian (ALE) approach was implemented to incorporate the axial and radial shrinkage effects in the FEM model. The results showed that the FEM model was satisfactorily able to predict the moisture content (R 2 > 0.97) and core temperature (R 2 > 0.98). Therefore, the proposed model can be used as a promising tool to optimise the drying process of banana from quality and efficiency points of view. Also, the model can be easily extended for drying of similar products with cylindrical shape. ARTICLE HISTORY

Microwave heating is an environmentally friendly method for killing pest insects and here its efficacy in the control of a pest species of dried fig and raisin was assessed. Dried fig and raisin samples were infested with Ephestia kuehniella Zeller (Lepidoptera: Pyralidae) larvae and heated in a microwave oven at power outputs of 450, 720, and 900 W for 20, 30, 40, and 50 s. Following exposure to the microwave treatments, larval mortality and changes to organoleptic properties, which indicate consumer preference and include aroma, color, sweetness, acerbity, fragility, stiffness, and overall acceptability, were assessed. Our results showed mortality rates were greatest with the highest degree and duration of microwave exposure, where 100% mortality was recorded at 900 W with an exposure time of 50 s. The sensory evaluations of the fruit showed that microwave heating had some effect on aroma, color, fragility, sweetness, and overall acceptability, but no effect on acerbity and stiffness in dried fig, whereas in raisin, there were no impacts on acerbity, stiffness, or sweetness, but aroma, color, fragility, and overall acceptability were affected. We conclude that application of lower intensities of microwave treatment may provide acceptable levels of pest control in stored dried fruit without an associated trade-off in the reduction in quality of sensory attributes.

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Raisins are one of the most important Iranian export products but are threatened by various storage pests. Because of the disadvantages of fumigants, we evaluated alternative microwave and ozone methods for their disinfection and the side effects on raisin qualities. To perform microwave disinfection, the studied raisin samples were exposed to microwave powers of 450, 720, and 900 W for 20, 30, 40, and 50 s. Also, ozone treatments included various combinations of ozone concentrations (2, 3, and 5 ppm) and exposure times (15, 30, 45, 60, and 90 min). An image processing technique was implemented to determine the color changes of raisins in terms of lightness, redness, yellowness, total color difference, chroma, and hue angle. The results revealed that increasing the microwave power and exposure time might lead to further changes of the previously mentioned color characteristics. Compared with the microwave treatments, ozone treatments had fewer effects on those features. Generally, microwave and ozone methods could successfully disinfect Oryzaephilus surinamensis in raisins, with acceptable changes in all the color characteristics. Hence, the previously mentioned methods are proposed as alternative chemical fumigants. HIGHLIGHTS

One of the most important products grown in Iran is walnut, while it can be threatened by some storage pests. Ozonation process is an environmentally friendly method for killing pest insects. Accordingly, ozone efficacy in the control of a pest species of walnut was assessed in this research. The selected walnut samples were infested with larvae of Plodia interpunctella (Hübner) and then subjected to various combinations of ozone concentrations (3, 4.5, and 6 ppm) and exposure times (20, 30, 40, and 50 min). Following the exposures to the ozone treatments, larval mortality rates and changes to the sensory properties (color, taste, smell, crispness, stiffness, and overall acceptability) of the walnut indicating consumer preference were evaluated. Our results revealed enhanced mortality rates of our pest with an increase in both ozone concentration and exposure time in a way that 99% mortality was recorded at the concentration and exposure time of 6 ppm and 50 min, respectively. The sensory assessments of the samples showed that ozone treatments had no significant impacts on the color, taste, crispness, stiffness, and overall acceptability of the product. Also, few changes were recorded for its smell, which could be improved over time after being exposed to the air. We concluded that application of higher ozone concentrations might provide acceptable levels of pest control for stored walnut with no possibly associated reduced trade-off for their quality attributes.

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