Effect of liquid fermentation on bread fortified with Lycium ruthenicum: a quality attribute and in vitro digestibility study

Abstract The aim of this study was to research the effect of yeast fermentation on the polyphenol content of Lycium ruthenicum (LR) to guide the production of bread with a lower digestibility. Liquid fermentation from 0 to 2 h significantly increased the phenolic, flavonoid and anthocyanin content of LR, while further liquid fermentation from 2 to 16 h had little additional effect. The addition of LR without prior liquid fermentation impaired the bread quality, while a prior liquid fermentation for at least 2 h improved the bread quality. The bread digestibility was decreased after adding LR, and it was further reduced with the extended liquid fermentation time. The results of this study indicate that adding LR with prior liquid fermentation to the dough during bread making could result in a higher quality and a lower digestibility.