Application of novel methods for quality improvement in explosion puffing drying of apple snacks

Abstract

In this study, vacuum drying (VD), microwave drying (MW) and freeze-drying (FD) alternatives to air drying (AD) were applied to apple samples before explosion puffing drying (EPD). The volumes of AD+EPD samples were determined 20% higher than the volume of AD samples. The porosity value and the average pore radius value were obtained by examining the SEM images with the MATLAB program. Porosity values were found between 0.41-0.82 for all drying processes applied. The lowest porosity was found at 180MW, and the highest porosity was found in the FD samples. It is seen that the porosity ratio increases as the microwave power per product increases. Rehydration rates of 180, 360 and 600MW samples were determined as 308, 320 and 336%, respectively. It contributed to the increase in rehydration due to the increase in the porosity of the product with the increase in power density per product in MW drying. There was an increase in the amount of TPC with the combined use of the EPD process. The highest ABTS and DPPH were determined in the FD, FD+EPD and 600MW+EPD samples, respectively. The pre-drying methods and parameters described in the study significantly affected the quality of apples in terms of their physical and chemical properties.