不同产地和品种发芽糙米的理化特性与食用品质研究

Study on physicochemical characteristics and edible quality of germinated brown rice from different origins and varieties

中文关键词:  糙米  发芽  品种  γ-氨基丁酸

英文关键词:brown rice  germination  γ-aminobutyric acid  origins  varieties

中文摘要:

      目的 研究发芽对12种不同产地与品种的糙米的理化特性和食用品质的影响。方法 采用不同浸泡液、低温等方式处理糙米, 使之发芽, 根据γ-氨基丁酸(gamma-aminobutyric acid, GABA)含量筛选出8种糙米。进一步比较其淀粉与直链淀粉、总酚含量, 以及感官品质、质构特性和糊化特性。结果 以5 mg/mL谷氨酸钠溶液浸泡发芽对发芽糙米中GABA的富集效果最好。其中, 蚌埠淮粳糯20的GABA含量可达(261.6±4.3) mg/100 g; 泰兴9108的GABA含量达(263.1±6.8) mg/100 g, 二者发芽率均可达96%。发芽使各品种糙米的色泽向黄红色偏移, 总酚含量显著增加(P<0.05), 淀粉与直链淀粉含量均显著降低(P<0.05)。发芽后, 糙米的糊化崩解值、回生值均显著下降(P<0.05)。不同品种的糙米米饭食用品质均好转, 表现为体积膨胀率显著提高(P<0.05)、硬度显著降低(P<0.05), 咀嚼性、胶着性降低, 黏性增强, 感官评分显著提高(P<0.05)。结论 地区和品种是影响发芽糙米GABA含量的重要因素, 发芽能有效改善糙米的营养与食用品质。

英文摘要:

      Objective To study the effects of germination on the physchemical properties and edible quality of brown rice. Methods Brown rice was pretreated by soaking in different solutions or low temperature to make it germinate. The γ-aminobutyric acid (GABA) content was determined to select 8 varities of brown rice for further study. The content of starch, amylose, total phenol, sensory quality, texture and gelatinization were further compared. Results The GABA content was mostly improved by soaking with 5 mg/mL sodium glutamate solution, the GABA content of the brown rice ‘Huainuo 20’ and ‘Nanjing 9108’ reached (261.6±4.3) and (263.1±6.8) mg/100 g, respectively. Meanwhile, the germination rates of these 2 varieties of brown rice both reached up to 96%. The color of all varieties of brown rice was changed to reddish and yellowish by the germination processing, and the content of total phenolics increased significantly (P<0.05), while the content of starch and amylose decreased significantly (P<0.05). After germination, the gelatinization disintegration values and retrogradation value of the brown rice both decreased significantly (P<0.05). The edible quality of different varieties of brown rice was improved after germination, which displayed by significantly increasing of the volume expansion rate and the stickiness (P<0.05) and significantly decreasing of the hardness, chewiness and adhesiveness. The sensory score was finally significantly improved (P<0.05). Conclusion Locality of grouth and variety are important factors affecting GABA content of germinated brown rice, and germination can effectively improve the nutrition and edible quality of brown rice.