Journal of Food Engineering, Vol.81, No.2, 318-329, 2007
Effects of combined pretreatments on drying kinetics and quality of potato chips undergoing low-pressure superheated steam drying
Due to an increasing demand from health-conscious consumers more attention has been placed on investigating alternative techniques to replace conventional deep-fat frying to produce health-friendly snack products including potato chips. Recently, low-pressure superheated steam drying (LPSSD) has proved to have potential to produce fat-free potato chips if performed in combination with appropriate pre-drying treatments. In this study, the influences of various pretreatments and drying temperature on the LPSSD drying kinetics and quality parameters of dried potato chips were investigated. LPSSD of potato chips underwent various combined pretreatments, i.e., (a) blanching, (b) combined blanching and freezing, (c) blanching followed by immersion in glycerol solution and then freezing, and (d) combined blanching, immersion in monoglyceride solution and freezing, were carried out at different drying temperatures (70, 80, and 90 degrees C) at an absolute pressure of 7 kPa. The quality of the dried chips was then evaluated in terms of colors, texture (hardness, toughness and crispness) and microstructure. In terms of the drying behavior and the dried product quality, LPSSD at 90 degrees C with combined blanching and freezing pretreatments was proposed as the most favorable conditions for drying potato chips. (c) 2006 Elsevier Ltd. All rights reserved.
Keywords:blanching;chemical pretreatments;combined pretreatments;colors;freezing;microstructure;texture