| Resistant starches (RSs) are food ingredient sources of fiber. Their fiber content is measured in vitro, which may not accurately reflect in vivo digestibility. Carbohydrate content of commercial starches (Hi-MaizeRTM 260 [HM], HylonRTM VII [HY] and Amioca [AM]) was determined in vivo. Fiber values for HM, HY and AM were: 32.8 g, 11.5 g and 0 g in vitro, 12.5 g, 40.8 g and 6.2 g from blood glucose study (n=10) and 18.7 g, 21.6 g and 1.7 g from ileostomy study (n=3). 13.4% and 43.5% of RS in HM and HY was recovered in effluent. Total bacterial count (TBC) was 109 CFU/ g of effluent and positive correlation (r=0.4955) existed between TBC and carbohydrates by difference for HM and HY. The in vitro AOAC 991.43 method underestimates fiber content in HY and AM and overestimates fiber content in HM and does not accurately reflect fiber content of RS products. |
