Bound phenolic compounds of whole cereal grains as a functional food component: part two

Abstract

Since they are eaten regularly, cereals based food make a significant contribution to the daily energy intake, meanwhile in whole-grain form they contribute to higher micronutrients intake that refined cereal products. The bound phenolic compounds, which are accumulated in cereal bran, play a key role in the duodenum, where they are transformed to the absorbable metabolites by microbial fermentation. In part two, an analysis of phenolic compounds is presented, with emphasis on the hydrolysis and extraction procedure for bound phenolic compounds, their quantification and identification. Due to poor bioavailability of non-extractable phenolic compounds, which critically limits the exploitation of their wide potential, the article also discusses techniques and new strategies that enable the release of phenolic compounds from insoluble bound forms during food processing. Two current approaches, germination and fermentation, are presented in more details. With transformation of bound phenolic compounds to more easily accessible free phenolic compounds, we also benefit from their antioxidant and antimicrobial efficacy in addition to a favorable anti-cancer effect on the colon. The awareness of consumers and their demand for healthier foods led to the exploration and incorporation of natural ingredients in the production of value added products. The extraction of ferulic acid from whole grain cereal products and its incorporation in functional food products is definitely an important area of future research.

Keywords

• whole-grain cereal products
• hydrolysis of bound phenolic compounds
• bioavailability of phenolic compounds
• germination
• fermentation
• functional foods