Nonthermal Processing Technologies for Stabilization and Enhancement of Bioactive Compounds in Foods

The processing of selected foods by nonthermal technologies is gaining relevance in the food industry because, in many cases, the final product keeps the nutritional value and other fresh-like characteristics of the original one. There are several nonthermal technologies including high pressure processing, pulsed electric fields, ultrasound, and cold plasma which are at different stages of development. The impact of a given technology on bioactive compounds is a good indicator to assess changes on the nutritional attributes of a given food product before and after processing. Quite frequently, it is mentioned that nonthermal technologies are very appropriate to process foods minimizing changes in quality attributes. This broad claim only applies for certain processing, packaging and storage conditions, and as expected, on the food product. There are extensive scientific publications on how these processes alter the food products, but the reported results have been attained by a disparity of treatments; therefore, comparisons of these results are difficult and sometimes useless. Nevertheless, the gathered information allows to identify, in many cases, valuable trends on how a process affects the different bioactive compounds of a given food product. At the same time, the available data allows to assert, that in general, nonthermal processing is a very sound alternative to conventional thermal treatments to minimize the impact of processing on bioactive compounds. This review summarizes and analyzes the effects of these processes on relevant bioactive compounds present in selected food products as reported in the scientific literature.