Investigation On Technology Of Processing And Storage Of Four Grain Chinese Steamed Breads

In order to broaden the food appilication fields of grains in China and develop Chinese steamed bread(CSB)with high addition of grains,the effect of adding different proportions of four grain flour(adzuki bean flour,extruded adzuki bean flour,millet flour and quinoa flour)on the quality of dough and CSBs were studied.The quality of CSBs during storage was evaluated through the technology of microwave sterilization and quick-frozen,and the study could provide scientific evidence for the industrial production of grain Chinese steamed bread(GCSB).The results of farinograph and pasting properties of four grain flour blended showed that adzuki bean flour(ABF)and millet flour(MF)had less neagative effect on farinograph properties of dough,however,extruded adzuki bean flour(EABF)and quinoa flour(QF)degaraded the stability of farinograph parameters.The increase of addition of four grain flour all had negative effect on pasting properties of flour blended.According to texture properties and sensory evaluation,the optimal amount of ABF,EABF,MF and QF were 20%,10%,20% and 10% respectively.The result of nutritional component analysis of four GCSBs showed that adzuki bean Chinese steamed bread(ACSB),extruded adzuki bean Chinese steamed bread(ECSB)and quinoa Chinese steamed bread(QCSB)ranked higher protein content,the three GCSBs could reduce the calorie intake of staple food.ECSB obtained balanced essential amino acids contents,the content of lysine and threonine was higher than that of wheat Chinese steamed bread(WCSB)especially.The α-glucosidase inhibitory activity of ECSB was significantly higher than that of WCSB,and ECSB can be as the stable food of diabetic or hyperglycemic population.The optimization test results of fermentation techology of four GCSBs showed that the optimal fermentation conditions of ACSB was that yeast addition was 0.8%,fermentation temperature was 38°C and fermentation time was 90 min.The optimal fermentation conditions of ECSB was that yeast addition was 1.0%,fermentation temperature was 38°C and fermentation time was 90 min.The optimal fermentation conditions of millet Chinese steamed bread(MCSB)was that yeast addition was 0.8%,fermentation temperature was 35°C and fermentation time was 90 min.The optimal fermentation conditions of QCSB was that yeast addition was 1.0%,fermentation temperature was 38°C and fermentation time was 90 min.The results of microbiological detection and quality evaluation indicated that the optimal microwave sterilization technology of ACSB was that sterilization power was700 W,sterilization time was 60 s and weight of dough was 50 g.The optimal microwave sterilization technology of ECSB was that sterilization power was 500 W,sterilization time was 60 s and weight of dough was 60 g.The optimal microwave sterilization technology of MCSB was that sterilization power was 500 W,sterilization time was 90 s and weight of dough was 40 g.The optimal microwave sterilization technology of QCSB was that sterilization power was 500 W,sterilization time was 90 s and weight of dough was 60 g.Compared to WCSB,the texture property and sensory evaluation score of ACSB and ECSB insiginificantly changed negatively.The hardness and springiness of MCSB and WCSB significantly increased and decreased,respectively,and QCSB could maintain well texture parameters and sensory quality for a long period storage time after microwave sterilization.The results of four quick-frozen GCSBs experiments indicated that the quick-frozen GCSBs obtained higher quality than that of untreated WCSB.However,the hardness and springiness of quick-frozen GCSBs was gradually increased and decreased during storage time respectively.Within 15 days of storage,four quick-frozen GCSBs could maintain high quality,especially ECSB and QCSB could maintain well quality in storage for 30 days.The addition of EABF and QF were beneficial to delay the aging of CSB.