Properties of Fermented Wheat Starch for Kuzu-mochi

Abstract

　Fermented wheat starch (FWS) is produced from starch as a byproduct of gluten manufacture. FWS is used in the traditional Japanese sweet, kuzu-mochi, which originates from the Edo period. The elastic but non-sticky texture of kuzu-mochi is attributable to the properties of FWS. To elucidate the characteristic properties of FWS, the comparison morphology, and physicochemical and pasting properties of starch with/without fermentation treatment were examined. Fermentation of wheat starch (WS) led to a decrease in the abundance of small starch granules, as small starch granules formed large aggregates. The degrees of damaged starch and amylose content in FWS were lower than those in unfermented WS. The λ_max of the iodine absorption spectrum of FWS was blue-shifted relative to that of WS. The maximum and final viscosities of FWS, and its consistency in the rapid visco analyzer viscogram were lower than those of WS. These results revealed that fermentation endows starch with low viscosity and the ability to retard retrogradation.