Effects of resistant starch type 4 supplementation of bread on in vitro glycemic index value, bile acid-binding capacity, and mineral bioavailability

Abstract

Background and objectives RS4 is an alternative dietary fiber source with some potential physiological benefits giving better quality end products. Common dietary fiber sources including bran usually have deteriorative effect on color, textural properties, and consumer acceptability of breads. This study was designed to investigate the effect of RS4 supplementation on the bread quality as well as mineral bioavailability, bile acid-binding capacity, in vitro glycemic index.

Findings Loaf volumes of the breads supplemented with RS4 were higher than the bread supplemented with wheat bran (WB). Among the bread samples, the one supplemented with WB had the darkest color and highest firmness values. During storage, WB supplementation caused the highest increase in bread firmness. RS4 supplementation caused higher total dietary fiber (TDF) and mineral bioavailability values and lower in vitro glycemic index than bran supplementation.

Conclusions RS4 supplementation of bread caused increases in TDF content, bile acid-binding capacity, and mineral bioavailability and has less deteriorative effect on the quality than WB supplementation. Breads supplemented with WB had a faster staling rate than the breads supplemented with RS4.

Significance and novelty Besides the better appearance and texture of the RS4 supplemented bread samples, the improvement in nutritional properties proved that RS4 is a better dietary fiber source than WB.