Current insights into non-thermal preservation technologies alternative to conventional high-temperature short-time pasteurization of drinking milk

Milk is an important nutritional food source characterized by a perishable nature and conventionally thermally treated to guarantee its safety. In recent years, an increasing focus on competing non-thermal food processing technologies has been driven mainly by consumers’ expectations for minimally processed products. Due to the heat sensitivity of milk, much research interest has been addressed to mild non-thermal pasteurization processing to keep safety, ‘fresh-like’ taste and to maintain the organoleptic qualities of raw milk. This review provides an overview of the current literature on non-thermal treatments as standalone alternative technologies to high-temperature short-time (HTST) pasteurization of drinking milk. Results of lab-scale experimentations suggest the feasibility of most emerging non-thermal processing technologies, including high hydrostatic pressure, pulsed electric field, cold plasma, cavitation and light-based technologies, as alternative to thermal treatment of drinking milk with premium in shelf life duration. Nevertheless, a series of regulatory, technological and economical hurdles hinder the industrial scaling-up for most of these substitutes. To date, only high hydrostatic pressure treatments are applied as alone alternative to HTSH pasteurization for processing of “cold pasteurized” drinking milk. Milk submitted to HTST treatment combined to ultraviolet light is currently accepted in EU countries as novel food.