EFFECTS OF DIFFERENT ADDITIVES ON RICE CAKE TEXTURE AND CAKE STALING

ABSTRACT MiGao, prepared from rice flour and sticky rice flour, is a kind of steam cooked Chinese cake. The purpose of this work was to evaluate the effect of different additives (carboxylmethyl cellulose [CMC], xanthan, β-amylase and α-amylase) on the MiGao quality during storage for 0, 1, 3 and 5 days at room temperature (25C). MiGao texture was determined by measure the hardness of MiGao crumb during storage. Differential scanning calorimetry (DSC) was used to follow changes of starch retrogradation in MiGao crumb. Among the preparations supplemented with additives as determined by texture and DSC measurements, followed the order of β-amylase > CMC > xanthan. In general, except when α-amylase was used, the overall acceptability of MiGao was always improved by the addition of additives. The simultaneous analysis of the firming and starch retrogradation results revealed that the anti-staling effect of additives might be due to the retardation in the starch retrogradation. PRACTICAL APPLICATIONS Freshly steamed MiGao are soft, pliable and elastic, but when kept at room temperature they stale within few hours and become tough and rigid. The shelf life of MiGao presents a major problem in China and can be costly to producer, distributor, consumer and the country in general. Concerning the aging or staling during storage, the hydrocolloids and enzymes tested reduce the amylopectin retrogradation, and they would therefore also be useful in rice cake processes.