Recent research and prospects of non-thermal physical technologies in green and high-efficient extraction of natural pigments: A review

Natural pigments are widely used in the food industry because of their unique sensory properties and nutritional value. However, natural pigments are susceptible to color change and loss of bioactivity due to their high temperature decomposition, which hinders the ideal application of traditional thermal technology in natural pigment retention related fields. Therefore, the food industry is gradually adopting non -thermal physical technologies (NPT) including ultrasonic technology (US), ultrahigh -pressure technology (UHP), supercritical fluid extraction technology (SFE), irradiation technology (IR), pulsed electric field technology (PEF) and cold plasma technology (CP), in order to achieve better results. Although several researches have been conducted, the underlying mechanism behind the effect of NPT on the structural of natural pigments remains elusive. In this review, the principle of NPT in extraction of different types of natural pigments is described. Moreover, the application of NPT in the extraction of natural pigments and the possible impact and connection of these technologies on the extraction yield, structure and bioactivities of natural pigments are examined. The aim of this review is to broaden the application of NPT in extracting natural pigments from food and agricultural byproducts.