Microwave frying and post-frying of French fries

Abstract

French fries are popular items in the diets of many countries, but the high oil content is a major health concern for consumers. Numerous novel frying techniques have been explored by the fast food service industry and the research community to address such concern. This research aimed to study the influence of microwave heating at two frequencies (2.45 and 5.85 GHz), both individually or in combination, in frying and post-frying on oil reduction in French fries. Results showed that microwave frying reduced the frying time by 30 - 40%, with equivalent product quality attributes in terms of oil content, color, and texture, as compared to deep-oil frying. Oil intake increased with increasing moisture loss during frying, regardless of the frying methods. Post-frying condition was the key to oil reduction. Specifically, a 60 s microwave heating after frying reduced the oil content by 18 - 23%. Compared to 2.45 GHz, microwaves at 5.85 GHz could produce French fries with significantly lower oil content (p ≤ 0.05) and better quality attributes such as color and texture. This study demosntrated the potential of microwave heating in production of deep-fried French fries with lower oil content and better quality.

Keywords: Color; Crispness; Frequency; Microwaves; Oil reduction; Solid-state microwave.