EVOLUTION OF FRUIT AND VEGETABLE DRYING TECHNOLOGIES: FROM TRADITIONAL DEHYDRATION TO AI-DRIVEN PRECISION PROCESSING AND CELLULAR STRESS RESPONSES AND MOLECULAR REGULATION

Abstract

Drying of fruit and vegetables has become an important strategy of post-harvest handling in extending shelf life, reducing storage and transport costs through decreasing moisture content and improving storability and portability of product. Beside a process of drying for removing water and changing mass transfer process of this material, Drying induces complex cellular, biochemical and molecular responses affecting nutritional quality, antioxidant capacity, structure and storability of food product. Some of these methods e.g. Sun drying, solar drying and hot air drying still widely used owing to the low operating cost and simplicity; However, there may lead to undesirable consequences including significant losses of nutrients, oxidatvie damages, collapse of structure and detrimental changes in quality. Advanced drying technologies such as infrared, microwave, radio frequency, Refractance Window, vacuum and heat-pump drying may enhance the retention of bioactive compounds by optimizing the rate of heat and mass transfer. Combining some complementary methods i.e. Hybrid drying technologies may reduce drying time and energy consumption. Artificial intelligence (AI), machine learning (ML), sensors technology and Industry 4.0 provide the means to monitor the drying process in real time and achieve intelligent adaptive optimization. Additionally, recent development on molecular and omics technologies will be promising for deciphering the genotype-specific drying behaviour, regulating stress responses and controlling secondary metabolites synthesis and metabolic pathways in the dehydration process of fruit and vegetable. The present review thus presents an integrated view of fruit and vegetable drying technologies, focusing on the intersection between the mechanisms of drying and the responses at the cellular, molecular and genotypic levels as well as intelligence of drying processes.