碾磨度对红米蒸煮、糊化特性、抗氧化活性 及其米饭质构、感官品质的影响

本文研究了适度碾磨对红米品质的影响,考察了碾磨度(0、2%、4%、6%、8%和10%)对红米蒸煮特性、糊化特性、抗氧化活性以及其米饭质构特性和感官品质的影响。结果表明,随着碾磨度的提高,红米的蒸煮时间逐渐缩短,4%碾磨度时显著(P<0.05)缩短为31 min,蒸煮吸水率、体积膨胀率和固形物损失率均呈现逐渐上升趋势;碾磨处理后红米的峰值糊化粘度(Peak Viscosity,PV)、崩解值(Breakdown,BD)和最终糊化粘度值(Final Viscosity,FV)均与碾磨度呈正相关,而红米饭的硬度随着碾磨度的增大呈下降趋势,4%碾磨度时硬度显著(P<0.05)降低35.28%,继续增加碾磨度时硬度无显著变化(P>0.05),弹性始终无明显变化,粘性呈现逐渐上升的趋势;红米中游离酚、黄酮的含量以及DPPH、ABTS自由基清除能力随着碾磨度的增加显著降低(P<0.05);在感官评定中,碾磨度0~4%时,感官评分增加到41.6分,碾磨度继续提高,感官得分变化差异不显著(P>0.05)。综上所述,碾磨度为4%时,红米具有较好的品质,能显著缩短蒸煮时间,降低熟米硬度,并保留较多的抗氧化物质,具有良好的感官品质。研究结果可以为适度碾磨红米产品的开发提供依据。

Effect of Milling Degree on Cooking Property,Pasting Property and Antioxidant Activity of Red Rice,Texture and Sensory Properties of Cooked Red Rice

In this study,red rice was subjected to moderate milling method(0,2%,4%,6%,8% and 10%)to investigate its cooking property,pasting properties,antioxidant activity,its cooked dish texture and sensory properties. Results indicated that the cooking time was gradually shortened as the milling degree grew and the lower value 31 min occurred at 4% treating level,while escalating trends were found in the cooking water uptake rate,volume expansion rate and solid loss rate. Peak viscosity(PV),breakdown(BD),and final viscosity(FV)were positively correlated with the milling degrees. The hardness decreased continuously with a significant(P<0.05)drop of 35.28% at 4%,but no significant variations were observed since 4%(P>0.05).Additionally,the elasticity remained stable under different milling degrees,while stickiness rose gradually. The contents of free phenol,flavonoids,DPPH and ABTS free radical scavenging ability decreased dramatically when increasing the milling degree(P<0.05). The sensory evaluation showed that sensory score increased significantly to 41.6 score when the milling degree ranged from 0 to 4%,but kept a relatively stable value since 4%. In conclusion,4% milling degree significantly shortened the cooking time,softened the cooked rice,retained more antioxidants and possessed good sensory qualities. Thus moderate milling method could exhibit potential for the promotion of red rice and the prospect of food industry.