The effect of pretreatments on the drying of persimmon with infrared energy

Abstract

AbstractThe effects of various pretreatments, including edible coatings, on drying kinetics and some physical quality parameters of persimmon varieties (Fuyu and Rojo Brillante) and differences between varieties were investigated. The experiments were conducted at an infrared radiation intensity of 1210 W m−2 and air velocity (v) of 1.5 m s−1. Drying time differed depending on pretreatments and varieties. Pretreatments generally shortened the Fuyu variety's drying time and increased the Rojo Brillante variety's drying time. Lower specific energy consumption and higher diffusion coefficient values were recorded for the Rojo Brillante variety compared to the Fuyu. In terms of quality parameters, the Fuyu variety generally obtained lower values for shrinkage. Rehydration rate was higher for the Rojo Brillante variety. Total color change was lower in the Rojo Brillante variety. Based on the pretreatments applied, xanthan gum gave better results in terms of operational parameters. In terms of quality parameters, ascorbic acid had better results for rehydration rate and shrinkage. For total color change, better results were obtained in arabic gum pretreatment. As a result, when an evaluation is made regarding variety differences and pretreatments applied, the Rojo Brillante variety can be recommended for drying.Practical applicationsPersimmon is a popular fruit in appearance, flavor, and rich nutritional content. The high moisture and sugar content in the fruit increases spoilage in a short time, making it difficult to consume in all seasons. For this reason, different preservation methods are being investigated to extend the shelf life. Sun drying and other drying methods developed as an alternative to these methods have many disadvantages. Different pretreatments prevent the negativities that occur in other drying methods. Especially, edible coatings can increase product quality by preserving color and appearance as well as controlling mass transfer, flavor, and aroma losses. This study investigated the effects of various pretreatments, including edible coatings, on drying kinetics and some physical quality parameters of persimmon varieties, as well the differences between varieties. Based on variety differences and pretreatments applied, the Rojo Brillante variety can be recommended for drying in terms of both processing and drying characteristics.