Effect of ultrasonic pretreatment on drying kinetics and physio-mechanical characteristics of peach slices

Peach, which is one of the most critical garden products in Iran has a lot of postharvest lesions. In this sense, processing the product would result in reducing the postharvest lesions. Recently, ultrasound waves have been widely applied as a new pretreatment method in drying food. Herein, we aim at investigating the effect of high power ultrasound pretreatment on the drying kinetics of peach slices. The effective moisture penetration coefficient, color changes and elastic modulus were investigated. The drying process was modeled using mathematical equations. The results showed that the ultrasound use as a pretreatment before drying reduces the drying time by up to 40%. The ultrasound treatment effect and the duration of their application on the color changes of the samples are not significant, and the reason for the color change is due to maillard reactions. The results of the effect of ultrasound pretreatment on the elastic modulus due to loading in the compression test showed that the application of pretreatment on the deformation of the samples is significant and reduced the modulus of elasticity by about 46%. The midilli model in different pretreatments, as compared to other models, had the best fitting with the experimental data. Moreover, the amount of effective diffusivity coefficient in the dried samples of peach slices, in different pretreatments, varies from 1.345 x 10(-9) to 5.370 x 10(-10) m(2) s(-1). In addition, it is worth mentioning that ultrasound pretreatment can be regarded as a promising approach. As far as food and agricultural products have typical structure and composition, ultrasound pretreatment application requires more through research. Practical Applications As compared to the untreated peach slices, a significant enhancement was witnessed in the ultrasound (US)-treated slices. Herein, a new method is proposed, which results in producing slices with an improved quality. Generally, peach-slice processing has been applied to get high-quality products.

Automated summary

This study investigated the effect of high power ultrasound pretreatment on the drying kinetics of peach slices. The results showed that ultrasound pretreatment reduced drying time by up to 40% and decreased the elastic modulus of the samples by about 46%. The color changes of the samples were not significant and were attributed to maillard reactions. The Midilli model had the best fitting with the experimental data. The effective diffusivity coefficient in the dried samples varied depending on the ultrasound pretreatment.