Bioactive properties of sorghum-based beverages from whole or refined grains

Abstract

Sorghum-based beverages were developed and the effects of decortication on nutritional composition and biofunctional properties after a simulated gastrointestinal digestion were analyzed. For that, white sorghum flours from whole (WS) and decorticated (DS) grains were obtained and used to prepare sorghum beverages. They were analyzed regarding chemical composition, minerals, and phenolic acid contents. Moreover, the bioaccessibility of phenolics, proteins, and the potential bioactivity (ABTS+ scavenging, ACE-I inhibition and DPP-IV inhibition) after a simulated gastrointestinal digestion were determined. The grain decortication increased the content of carbohydrates and Fe in the flour, but decreased all the other compounds analyzed. Gallic and ferulic acids were the most abundant free and bound phenolics, respectively. WS-beverage exhibited higher gallic acid bioaccessibility, while DS presented higher p-coumaric acid bioaccessibility, with no differences for ferulic acid. DS-beverage showed higher peptide bioaccessibility than WS, probably because of the higher degree of hydrolysis of proteins from refined flour. Regarding bioactive properties, WS- beverage presented 20% more ABTS scavenging than DS, possibly related to the higher phenolic content. On the other hand, DS-beverage presented higher ACE-I and DPP-IV inhibition than WS (40 and 100% more, respectively) because of the generation of bioactive peptides. Whole or refined sorghum could be used to produce beverages analogs to milk, with health potential benefits.