Optimization of the Blanching of Potato (Solanum tuberosum L) Slices by Response Surface Methodology: Effect on the Vitamin C Content and Drying Kinetics

Abstract

Potatoes (S. tuberosum L) are one of the most important tuber crops in the world. However, their high moisture content and inadequate storage and processing techniques have a negative influence on their quality and availability throughout the year. This work was carried out to optimize the blanching behavior and drying kinetics of potato slices. Fresh potato slices (5, 10, and 15 mm) were blanched at 70, 80, and 90 °C for 1, 3, and 5 minutes following a 3^k level full factorial design. The loss of Vitamin C was used as a quality marker for the optimization process. The influence of blanching on the drying behavior of potato slices was studied at 50, 60, and 70 °C. Results showed that blanching parameters had a significant (P < 0.05) effect on Vitamin C loss. Optimum blanching conditions were a blanching temperature of 80 °C, a blanching time of 3 minutes, and a slice thickness of 10 mm, which resulted in an average loss of Vitamin C of about 2.6%. Drying data were successfully fitted to three different thin layer drying models. The use of blanching as a pretreatment before the drying of potatoes is recommended because it reduces the drying time by 30%.