Comparison of quality aspects and energy consumption of restructured taro and potato chips under three drying methods

Due to a high variety of health effects, nutritive snacks based on carbohydrate and dietary fibers are receiving growing attention in snack food production. The restructured chips were prepared by mixing of rose powder and other ingredients into restructured taro (TR) and potato (PR). Restructured (TR) and (PR) chips were dried using freeze-drying (FD), infrared radiation drying (IRD), and hybrid infrared-assisted freeze-drying (IRFD) in this study. Investigation of three drying methods in terms of the main quality parameters, namely color, odor, texture, water activity, expansion ratio (ER), and bulk density as well as other quality aspects and energy consumption of two kinds of chips were compared. FD took the highest energy consumption and longest processing time together with the lowest drying rate among them. IRFD chips had the lowest water activity (a(w)), the total color difference (Delta E), and the highest overall acceptability score of sensory evaluation among them. IRFD had higher crispness and lower energy consumption than FD alone. Moreover, there were no significant differences in crispness between IRFD and commercial chips. IRFD chips contributed better product quality over IRD chips. Results of this work showed that IRFD method has the potential to keep high-quality aspects for dried restructured chips with saving energy consumption. Practical applications Infrared-assisted freeze-drying (IRFD) can save 25-29% of drying time and 43-46% of the total energy consumption in comparison of FD with keeping high-quality aspects and better product quality than IRD. IRFD method is a novel method for making food products with better color, maintains high-quality, and less drying time. The research found that hybrid IRFD can produce high-quality aspects as well as save time and energy consumption for large-scale industrial production of restructured chips and various food products.