Abstract
Deep-fried foods (e.g., French fries, potato/veggie crisps) are popular among consumers. Recently, there has been an increased interest in the application of Pulsed Electric Fields (PEF) technology as a pretreatment of plant-based foods prior to deep-frying to improve quality (e.g., lower browning tendency and oil uptake) and reduce production costs (e.g., better water and energy efficiencies). However, the influence of a PEF pretreatment on the frying process and related chemical reactions for food materials is still not fully understood. PEF treatment of plant tissue causes structural modifications, which are likely to influence heat, mass and momentum transfers, as well as altering the rate of chemical reactions, during the frying process. Detailed insights into the frying process in terms of heat, mass (water and oil) and momentum transfers are outlined, in conjunction with the development of Maillard reaction and starch gelatinisation during frying. These changes occur during frying and consequently will impact on oil uptake, moisture content, colour, texture and the amount of contaminants in the fried foods, as well as the fried oil, and hence, the effects of PEF pretreatment on these quality properties of a variety of fried plant-based foods are summarised. Different mathematical models to potentially describe the influence of PEF on the frying process of plant-based foods and to predict the quality parameters of fried foods produced from PEF-treated plant materials are addressed.
Highlights
Pulsed Electric Fields (PEF) technology applies short and repetitive electric pulses of high voltage to food materials placed between two conducting electrodes, leading to electroporation of cells [1]
The purpose of this review is to provide an overview of the different mechanisms and reactions that occur during frying processes and explain how PEF pretreatment of plant materials can result in various quality improvements in the final products
Despite there being no studies directly reporting the influence of PEF pretreatment on momentum transfer in plant materials during frying, Dellarosa et al [44] have shown that PEF could help to gain momentum to increase mass transfer in plant-based foods during processing, which suggests that the momentum transfer in PEF-treated plants would increase during frying
Summary
Pulsed Electric Fields (PEF) technology applies short (μs or ms) and repetitive electric pulses of high voltage to food materials placed between two conducting electrodes, leading to electroporation of cells [1]. Apart from heat, mass and momentum transfers, chemical constituents (e.g., starch, reducing sugars, amino acids and water) within plant tissue react with each other during frying, and physical reactions (e.g., water evaporation and oil uptake) occur accompanied by structural changes [17]. Frying models, especially those built based on universal physical laws, may provide a better understanding of the frying process and its mechanism [15,18]. The review will be concluded by discussing the potential use of frying models to explore the effect of PEF on frying to benefit further research and industry application
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call