Effects of non-thermal processing techniques on cereal bran: Focus on changes in bran structure and polyphenol release

Cereal bran, a nutrient-rich by-product of grain processing, contains high levels of dietary fiber, polyphenols, and bioactive compounds, offering antioxidant and anti-inflammatory benefits. However, its rigid cell wall structure limits the release of bioactive compounds, requiring modification for food applications. Conventional thermal processing degrades heat-sensitive components and reduces polyphenol yields, whereas non-thermal methods (physical, chemical, and biological) better preserve and enhance the release of bioactive compounds. This review examines the impact of non-thermal processing on bran structure and polyphenol release, focusing on the mechanisms, structural changes, and safety implications. It also compares combined non-thermal methods with single treatments and explores structure-function relationships to support bran's use in functional foods.