Whole grain: an open issue

Given the well-known health benefits of whole grain (WG) consumption, consumers are increasingly demanding WG versions of many cereal-based products. According to the “American Association of Cereal Chemists (AACC)” the term “whole grain” is defined as the “intact, ground, cracked, or flaked caryopsis of the grain whose principal components, the starchy endosperm, germ, and bran, are present in the same relative proportions as they exist in the intact grain”. Currently, in most cases, whole meal type flours are obtained by recombining appropriate amounts of bran and middlings with refined flours. However, this recombination results in products with very different compositional and sensory characteristics and technological properties. Evaluating the WG content of wheat products by measuring specific fractions related to different wheat components is a current and perceived concern of the food industry. Indeed, commercial products labelled as “WG” may actually contain a substantial fraction of refined wheat. In processed WG products, the grain tissue ratios cannot be traceably due to a lack of markers of different kernel fractions, such as germ. The identification of specific lipid biomarkers could be effective in assessing the wheat germ content of wheat-based products. However, the presence of germ represents an important source of bioactive compounds but its lipid content could compromise the quality and the shelf life of WG flours and products. Therefore, while the regular consumption of WGs is recommended in many dietary guidelines (1), WG flour and its products possess several unique challenges to the milling and related industries.