Traditional and Non-Conventional Methods of Pre-Treatment of Biological Raw Materials for Drying Food

Pre-treatment before drying is a crucial phase in food processing. This review highlights key traditional and innovative pre-treatment methods, focusing on their mechanisms of action at the cellular and tissue levels. This discourse examines innovative technologies with significant promise across various applications, as well as widely recognised methodologies. These include cold plasma, ultrasonication, pulsed electric fields, high-pressure processing, UV-C light, pulsed light, and coating techniques. It addresses biological components that act as barriers to mass transfer, thereby significantly influencing the efficiency of moisture evaporation. Understanding these interactions is crucial for optimising drying processes and enhancing the quality of dried food. Key pre-treatment parameters that affect outcomes are analysed and must be tailored to the specific characteristics of biological materials, which often require individualised adjustments. Each method is evaluated against goals like accelerated drying, microbiological purity, enzyme inactivation, and preservation of active components, emphasising the need for a targeted optimisation approach. The classification of biological materials into distinct categories has been proposed based on their structural and integumentary characteristics. The research outlines effective methodologies for each material type and pre-treatment purpose. This analysis also incorporates an economic perspective, considering the initial investment and operational costs of implementing the proposed methods.