7 - Impact of processing on mineral bioaccessibility/bioavailability

Abstract

A review is made of the influence of processing on the bioaccessibility/bioavailability of macrominerals (Ca, P, Mg and K) and microminerals (Fe, Cu, Zn and Se). In vegetable foods, household processes (dehulling, soaking, germination and fermentation) alone or with thermal processing increase mineral bioaccessibility, mainly referred to Fe, Cu, Zn, Se and Ca. The application of thermal processing to vegetable foods has different effects upon mineral bioaccessibility, with an overall increase in Ca and Fe and a decrease in Se. In turn, there is a general positive impact upon mineral bioaccessibility in animal foods when conventional thermal processing is used with shorter times and lower temperatures. High pressure processing (HPP) (non-conventional processing) shows conflicting results, but may be an alternative to thermal treatment for improving mineral bioaccessibility and in vitro bioavailability. No general guidelines can be given to improve mineral bioaccessibility/bioavailability, though proper consideration of the type and conditions of processing, and of the food matrix composition and structure, is required.