PRODUCTION OF SHORT-CHAIN FATTY-ACIDS FROM RESISTANT STARCH IN A PIG MODEL

This study was performed to estimate the pool of SCFA produced in the digestive tract of growing pigs after the consumption of diets contain ing different sources of resistant starch (RS) (15 g per meal) (potato starch (PoS), high amylose maize starch (HS) and retrograded extruded HS (RHS)). SCFA production in vitro was respectively 19, 23 and 21 mm ol g(-1) of fermented PoS, HS and RHS. The highest butyric acid produc tion was observed with PoS. Fifty six, 36 and 19% respectively of inge sted PoS, HS and RHS escaped digestion in the small intestine, whereas residual starch was completely fermented in the large bowel. Luminal total SCFA in the caeco-colon 7 h after the experimental meal were res pectively 33, 78 and 105 mmol for PoS, HS and RHS, with PoS providing the highest production of butyric acid. Theoretical in vivo SCFA produ ction, calculated on the basis of results for in vitro fermentation an d ileal digestibility, differed from in vivo results for PoS (+ 65%) a nd HS (-13%), but not for RHS. This study reveals different rates of d isappearance of RS both in vitro and in vivo. (C) 1998 SCI.