The microbial fermentation characteristics depend on both carbohydrate source and heat processing: a model experiment with ileo-cannulated pigs

Abstract

The effects of carbohydrate (CHO) source and processing (extrusion cooking) on large intestinal fermentation products were studied in ileo-cannulated pigs as a model for humans. Pigs were fed diets containing barley, pea or a mixture of potato starch:wheat bran (PSWB) either raw or extrusion cooked. Extrusion cooking reduced the amount of starch fermented in the large intestine by 52–96% depending on the CHO source and the total pool of butyrate in the distal small intestine + large intestine by on average 60% across diets. Overall, extrusion cooking caused a shift in the composition of short-chain fatty acids (SCFA) produced towards more acetate and less propionate and butyrate. The CHO source and processing highly affected the fermentation characteristics and extrusion cooking generally reduced large intestinal fermentation and resulted in a less desirable composition of the fermentation products. The latter outcome is non-conducive to a healthy large intestinal environment and its resulting metabolic health.

Graphical Abstract

Keywords:

• Starch
• extrusion cooking
• fermentation products
• butyrate
• dietary fibre

Acknowledgements

The financial support for this investigation from The Danish Agricultural and Veterinary Research Council is gratefully acknowledged.

Disclosure statement

The authors declare no conflict of interest.

Additional information

Funding

The financial support for this investigation from The Danish Agricultural and Veterinary Research Council is gratefully acknowledged.