Freeze-Drying of Fruits and Vegetables in Food Industry: Effects on Phytochemicals and Bioactive Properties Attributes - A Comprehensive Review

Freeze-drying has become an important technology used to extend shelf-life and to preserve food nutritional quality. It is most recommended for high-value foods and those containing heat-sensitive ingredients. However, to our knowledge, there are significant differences in the retention of phytochemicals in various fruits and vegetables during freeze-drying, which need to be summarized and explained. Thus,the evolution of the bioactive substances and free radical scavenging abilities of fruits and vegetables based on the freeze-drying procedure will be explored in this review. Furthermore, the stability of bioactive ingredients in freeze-dried products during storage will be also deeply reviewed in this paper by comparing the presented studies in these aspects. The comprehensive review of the research progress of freeze-drying techniques and the challenges in developing freeze-dried products is discussed.