Wheat bran thermal treatment in a hot air oven does not affect the fermentation and colonisation process by human faecal microbiota. (September 2019)

• Record Type: Journal Article
• Authors: De Paepe, Kim; Verspreet, Joran; Courtin, Christophe M.; Van de Wiele, Tom
• Is Part Of: Journal of functional foods. Volume 60(2019)
• Publication Date: 2019-09
• Subjects: Human gut microbiome -- Dietary fibre -- Prebiotics -- Wheat bran-attached microbial community -- Wheat bran toasting -- Wheat bran surface hydrophobicity; Functional foods -- Analysis -- Periodicals; Food -- Biotechnology -- Periodicals; Nutrition -- Periodicals; 613.2
• DOI: 10.1016/j.jff.2019.103440
• Languages: English
• ISSNs: 1756-4646

Abstract

Graphical abstract: Highlights: Heat treatment in a hot air oven (170 °C, 30′) conserves wheat bran prebiotic action. Heat-induced changes in wheat bran hydrophobicity are reverted during digestion. Wheat bran fermentation and colonisation by faecal microbiota is unaffected by heat treatment. The wheat bran-attached and 'luminal' microbial communities are distinct. Abstract: Wheat bran, rich in dietary fibre, serves as an important fermentation substrate and provides a unique colonisation site for the human gut microbiota. Dry heat treatment is frequently applied to stabilise wheat bran by inactivating endogenous enzymes that otherwise cause rancidity. It, however, alters wheat bran surface properties, which might affect wheat bran colonisation and fermentation, possibly interfering with the production of health promoting microbial metabolites. We found that the heat-induced increased bran surface hydrophobicity was obliterated during in vitro gastrointestinal digestion. As a consequence, the prebiotic action was preserved during in vitro batch incubations with faecal microbiota from ten healthy individuals. The microbial community both in suspension and colonising the insoluble wheat bran residue, remained unaffected and sustained a similar microbial activity compared to unmodified wheat bran. The wheat-bran attached and luminal community differed significantly, confirming our previous results and this was unaffected by dry heat-treatment.