Effects of particle size reduction of insoluble fibres by micron technology on various caecal and faecal indices

BACKGROUND: Previous findings demonstrated that particle size reduction of insoluble fibre materials (i.e. starfruit insoluble fibre-rich fraction and cellulose) to micro-sizes effectively enhanced their physicochemical properties, which provided clues to their physiological functions. The aim of the present study was to investigate the effects of particle size reduction of these insoluble fibres by micron technology on indices of bowel health. RESULTS: Feeding of the micronised fibres (9.68-14.3 mu m), especially those prepared by high-pressure micronisation, effectively (P < 0.05) improved various caecal and faecal indices, such as decreasing the caecal ammonia concentration (by 20.0-30.0%), increasing the faecal output (135-150%) and moisture content (143-1571/0) and lowering the activities of undesired beta-D-glucosidase (by 39.2-43.6%) and P-D-glucuronidase (by 71.4-77.5%) in faeces of hamsters. Relationships between physicochemical properties and physiological functions of the micronised fibres were considered. The results also demonstrated that the type, processing and related particle size of insoluble fibres were important factors affecting their physicochemical properties and physiological functions. CONCLUSION: The consumption of micronised insoluble fibres at 5% level might exert a favourable effect on improving various caecal and faecal indices. The results of this study provide some hints on potential applications of micron technology in the food industry. (c) 2007 Society of Chemical Industry.