Pulsed electric field as a pre-treatment in food freezing processes: Fundamentals, mechanisms, applications and impacts on frozen food quality

Abstract

Controlling freezing rates, ice crystal size distribution, and ensuring uniform freezing are critical for minimizing microstructural damage and preserving the sensory and nutritional quality of frozen foods. Pulsed electric field (PEF) technology has emerged as a promising pre-treatment for enhancing freezing processes and the quality of foods subjected to freezing. In this context, this review offers a comprehensive overview of recent advancements and applications of PEF technology as a pre-treatment in the food freezing industry. The mechanisms of PEF action on freezing processes, including its effects on ice crystal formation, tissue integrity, and impregnation of cryoprotectants, are discussed. Furthermore, the impact of PEF pre-treatment on various food matrices, such as fruits, vegetables, and meats, is examined, highlighting improvements in texture, color, nutrient retention, and shelf-life extension. Challenges and opportunities associated with integrating PEF technology into freezing operations are also addressed. Although research on PEF application remains limited in terms of the variety of foods studied, existing studies demonstrate that electroporation significantly enhances the efficiency and quality of the freezing process, which relies on heat and mass transfer. PEF pre-treatment can accelerate freezing processes, resulting in shorter freezing times and improved production efficiency. Additionally, it can enhance the retention of food quality attributes such as texture, flavor, functionality, and nutritional content. Overall, PEF pre-treatment shows potential as a sustainable and effective tool for enhancing freezing processes and improving the quality of frozen foods. However, challenges related to process scalability, equipment costs, and integration with existing production lines must be addressed for successful industrial-scale implementation.