Recent developments in frying technologies applied to fresh foods

Abstract

BackgroundDeep-fat frying is one of the most popular food processing methods worldwide. It involves simultaneous transfer of heat and mass at high temperature. Typical fried products tend to have bright color, crisp texture and delicious taste. In fact, fried foods contain large amount of oil, calories and acrylamide which are burden to health. It is necessary to develop innovative frying technologies to reduce oil absorption during frying process, thus obtain healthier fried products with low oil content. Scope and approachControl of oil content can be achieved by developing pretreatment technologies, innovative frying technologies as well as post-frying processing technologies to produce products with less oil content and calories, while maintaining similar qualities, good flavor and edibility. Mechanism of oil absorption as well as the heat and mass transfer processes that occur during frying are helpful to understand how oil penetrates in fried foods. Frying technologies can be optimized to substantially reduce the oil content in fried foods. Key findings and conclusionsNovel alternative frying technologies, such as microwave-assisted vacuum frying (MVF), pulse-spouted microwave vacuum frying and power ultrasound and microwave assisted vacuum frying (USMVF) have proved to be efficient to produce products with lower oil content and better texture characteristics compared to conventional frying. In addition, different pretreatment technologies, such as pulse electric field (PEF) and infrared radiation as well as post-frying processing can be applied to frying process to achieve synergistic effect.