茶花蜂花粉酸羊乳发酵和冷藏期间品质及抗氧化活性研究

Quality and antioxidant activity of goat milk yogurt with Camellia sinensis bee pollen addition during fermentation and refrigeration

以中国特色茶花蜂花粉为原料制备水提物并应用于功能性酸羊乳开发,研究蜂花粉添加以及β-环状糊精(β-cyclodextrin,β-CD)保护剂处理蜂花粉对酸羊乳感官、酸度、乳酸菌数、持水力、质构和抗氧化指标的影响,并探究产品冷藏期间品质及抗氧化活性动态变化。结果表明:适量添加茶花蜂花粉(1%、2%)提高了酸羊乳感官品质,尤其经β-CD处理后,产品色泽、风味及口感显著提升;茶花蜂花粉可促进乳酸菌发酵产酸,但对乳酸菌数、持水力、硬度、稠度、内聚性及黏性有微弱不利影响,而β-CD处理则会产生明显积极效果;无论β-CD处理与否,茶花蜂花粉酸羊乳产品抗氧化活性均显著增强。冷藏过程中,β-CD-茶花蜂花粉酸羊乳在货架期内保持较好感官品质,酸度有所增加但小于100°T;尤其添加2%β-CD-茶花蜂花粉有利于减缓产品冷藏期间活菌数变少、持水力及质构特性变差现象,DPPH自由基清除率、FRAP总抗氧化值及Fe^(2+)螯合能力至冷藏结束分别提高33.41%、30.91%、47.85%。茶花蜂花粉经β-CD保护处理后制得的酸羊乳具有优良的产品品质及抗氧化活性,是一种非常有潜力的新型健康酸乳产品。

The Chinese characteristic Camellia sinensis bee pollen(CBP) was selected to prepare aqueous extracts and then applied to develop functional goat milk yogurt.The effects of CBP addition,which was treated by β-cyclodextrin(β-CD) or not,on sensory quality,acidity,lactic acid bacteria count,water holding capacity,textural characteristics and antioxidant activities of goat milk yogurt was studied,and the dynamic changes of quality and antioxidant activity of products during refrigeration were also explored.Proper addition of CBP(1%,2%) could improve sensory quality of goat milk yogurt,especially after β-CD treatment,the color,flavor and taste of products were significantly increased.The CBP promoted lactic acid bacteria to produce more lactic acid but had slight negative effects on lactic acid bacteria counts,water holding capacity,hardness,consistency,cohesiveness and adhesiveness,while β-CD treatment could bring distinctly positive action.Whether treatment by β-CD or not,the antioxidant activity of goat milk yogurt was remarkably enhanced.During refrigeration of goat milk yogurt added β-CD-CBP,sensory quality was well maintained,acidity increased but less than 100 °T;especially for the product with 2% CBP,the decrease of lactic acid bacteria counts,water holding capacity and textural characteristics was relieved,and the DPPH· scavenging rate,FRAP value,and Fe^(2+) chelating ability increased by 33.41%,30.91% and 47.85% respectively until the end of refrigeration.The goat milk yogurt added β-CD-CBP has excellent quality characteristics and antioxidant activities,which is expected to become a promising new healthy yogurt.