青稞-绿豆格瓦斯的制备及其抗氧化活性研究

Study on Preparation and Antioxidant Activity of Hullessbarley-Mung Beans Kvass

为了丰富格瓦斯的品种和加强其保健功能,以青稞和绿豆为原料,通过发酵来制备新型的格瓦斯(HM-K),设计单因素和正交试验对其发酵工艺进行优化,对其抗氧化特性和抗氧化机理展开了研究,并与其它三种格瓦斯(HB-K、WH-K和QL-K)进行了对比分析。研究结果发现,青稞-绿豆格瓦斯(HM-K)的最佳发酵工艺是:选择同步发酵法,以保加利亚乳杆菌与生香酵母为混合发酵剂,青稞与绿豆比例为7∶3,菌剂添加量为0. 25%(两种菌各为0. 125%),发酵温度为30℃,发酵时间为24 h,所得产品呈棕黄色,酯香味和醇香味突出,有青稞和绿豆的特有香味; HM-K与HB-K具有较高的DPPH自由基和羟基自由基(·OH-)清除力、还原力和总抗氧化力,特别是HM-K的指标皆明显高于WH-K与QL-K(p <0. 05); HM-K的总黄酮含量最高(125. 21 mg/L),其次是HB-K(97. 46 mg/L),两者明显高于WH-K和QL-K(p <0. 05),HM-K与HB-K的总黄酮含量间也存在显著差异(p <0. 05);而HM-K(137. 46 mg/L)与HB-K(135. 21 mg/L)的总酚含量差距不大,但都明显高于WH-K和QL-K (p <0. 05)。研究结果表明可能是原料和发酵工艺的差异导致了不同格瓦斯之间总黄酮和总酚含量的差异,从而引起其抗氧化特性的差异。

A new type of gassy( HM-K) is prepared by the fermentation of hullessbarley and mung beans as the raw materials. The fermentation process is optimized by single factor and orthogonal test,and the anti-oxidation property and the anti-oxidation mechanism are studied and compared with the other three kinds of gas( HB-K,WH-K and QL-K). The results show that the best fermentation technology of HM-K is to select synchronous fermentation method,using Lactobacillus bulgaricus. and Fragrant yeast as mixed starter,and the ratio of hullessbarley to mung bean is 7 ∶ 3,the addition of inoculants is0. 25%( 0. 125% for both bacteria),the fermentation temperature is 30 ℃ and the fermentation time is 24 h. The obtained product is brown yellow with ester fragrance and the alcohol flavor being prominent and has the unique flavor of the highland barley and the mung bean. HM-K and WH-K have higher DPPH free radicals and hydroxyl radical(·OH-) clearance force,reducing force and total anti-oxidation force,and in particular the index of HM-K is obviously higher than that of WH-K and QL-K( p < 0. 05). The content of total flavonoids in HM-K is the highest( 125. 21 mg/L),followed by HB-K( 97. 46 mg/L),which is significantly higher than that in WH-K and QL-K( p < 0. 05) and there is also significant difference between HM-K and HB-K( p < 0. 05). The total phenol contents of HM-K( 137. 46 mg/L) and HB-K( 135. 21 mg/L) are not significantly different,but both of them are significantly higher than those of WH-K and QL-K( p < 0. 05). The results show that the difference of raw materials and fermentation technology results in the difference intotal flavonoids and total phenol contents between different Kvass,which leads to the difference of antioxidant properties.