加速陈化对稻谷制备米饭和米粉品质的影响

Effect of accelerated aging on the quality of rice and rice noodles

为了探究稻谷在陈化期间其米饭和米粉食用品质的变化,采用人工气候箱模拟典型的高温高湿(35℃,RH 75%)储藏生态区的温度、湿度来加速陈化稻谷,在12个月的储藏期中定期取出样品分别制成米饭和米粉,测定其蒸煮和质构特性指标并对其食用品质进行感官评价,研究加速陈化对各指标的影响。结果表明:随着储藏时间的延长,稻谷的米汤干物质、米汤p H值和米汤碘蓝值均呈现不断下降的趋势;米粉的吸水率和粉汤浊度随着储藏时间的延长呈现先升后降的趋势,蒸煮损失率和熟断条率先下降后基本保持稳定。在质构特性研究中,随着储藏时间的延长,米饭的硬度不断增大,黏性和弹性呈下降趋势;米粉的硬度和咀嚼性不断增大,黏性呈下降趋势。在感官评价检测中,米饭的感官评分随储藏时间延长不断下降,米粉的感官评分则先升后降。综合米饭、米粉的品质变化规律可知,随储藏时间的延长,米饭的适口性不断下降,而米粉的适口性呈现先升后降的趋势。

Paddy is one of the main food crops in many countries. It is usually produced into rice and traditional rice products such as rice noodles( rice-flour noodles) that are popular in the south of China,such as Hunan and Guangdong province. However,rice and rice noodles( rice-flour noodles) made from rice at different degrees of aging have different tastes. To explore the changes of edible qualities of rice and rice noodles during the aging of paddy,and to find the best way of eating paddy with different aging degrees,an artificial climate box was used to simulate the temperature and humidity of the typical high-temperature and highhumidity( 35 ℃,RH 75%) storage ecological area to accelerate the aging of rice. The paddy was stored for12 months,and samples were taken out every month,weighed,washed,and steamed to make rice. After rice hulling,rice milling,and steaming,the rice was made into rice noodles. The cooking and texture characteristics of rice and rice noodles were measured and their eating quality was determined by sensory evaluation of,and the effect of accelerated aging on the changes of various indexes was studied. The results showed that with the extension of storage time,both the dry matter of rice soup and the pH value showed a downward trend,indicating that the taste and smell of rice began to deteriorate and the taste became sour. The iodine blue value of rice soup also decreased. The decline throughout the storage period indicated that the soluble amylose content in the rice grains gradually decreased. The water absorption of rice noodles showed an upward trend from the 2 th to 10 th month of storage,indicating that the taste of rice noodles began to become soft and waxy,and it began to decrease from the 10 th to 12 th month,indicating that the taste of rice noodles began to harden. The turbidity of the powder soup showed an upward trend in the first 3 months of storage,and in the following 4 th to 12 th month,an overall downward trend was observed;both the cooking loss rate and the cooked section rate dropped sharply in the first 4 months of storage,indicating that the cooking resistance of rice noodles was improved and remained stable in the later storage period. In the study of texture properties,as the storage time increases,the hardness of rice continued to increase,and the viscosity and elasticity continued to decrease;the hardness and chewiness of rice noodles continued to increase,and the viscosity continued to decrease. In the sensory evaluation test,the sensory score of rice continued to decline with the prolonged storage time,and the sensory score of rice noodles began to decline after reaching the maximum value at the 8 th month. In general,with the extension of storage time,the palatability of rice continued to decline,while the palatability of rice noodles showed a trend of increasing first and then decreasing. Therefore,rice made from newly harvested paddy will have better edible quality,and rice noodles with better edible quality can be made from paddy stored for a certain period of time.