姜黄素-牛血清白蛋白复合物对牦牛乳干酪品质的影响

本研究旨在探讨牛血清白蛋白构建包封姜黄素的纳米复合物作为提高牦牛乳干酪成熟品质的潜在策略，试验测定了牦牛乳干酪的水分、灰分、粗蛋白、粗脂肪、pH、pH4.6醋酸盐缓冲液可溶性氮、12%三氯乙酸溶液可溶性氮、硫代巴比妥酸反应物、酸价以及感官指标。结果表明:姜黄素-牛血清白蛋白纳米复合物的存在能够显著提升牦牛乳干酪的水分与蛋白质含量（P<0.05），还能促进乳酸菌的增殖并抑制杂菌生长，有助于牦牛乳干酪中脂肪与蛋白质的分解，形成短链脂肪酸和多肽，呈现较好的独特风味；而复合物添加量过高会减弱益生效果，降低脂肪和蛋白分解效率，同时也引起干酪色泽发黄而降低感官评分。在成熟过程初期，感官评分显著提升（P<0.05）得益于蛋白质水解反应以及脂肪分解反应的发生，但成熟期过长会导致苦味小肽等物质的堆积，形成不良风味，影响感官品质。总体来讲，姜黄素-牛血清白蛋白复合物添加有助于牦牛乳干酪品质的提升，且复合物添加量为4%，成熟时间为60 d时，干酪产品品质最佳。

Effect of Curcumin-Bovine Serum Albumin Complex on the Quality of Yak Milk Cheese

The purpose of this study was to investigate the construction of curcumin encapsulated nanocomposite based on bovine serum albumin (BSA) could be a potential strategy to improve the ripening quality of yak cheese. The moisture, ash, crude protein, crude fat, pH value, pH4.6 acetate buffer soluble nitrogen, 12% trichloroacetic acid solution soluble nitrogen, thiobarbituric acid reactant, acid value and sensory index of yak milk cheese were determined. The results showed that the presence of curcumin-BSA nanocomplex could significantly improve the moisture and protein content of yak milk cheese (P<0.05）, promote the proliferation of lactic acid bacteria and inhibit the growth of hybrid bacteria, contribute to the decomposition of fat and protein in yak milk cheese, and form short-chain fatty acids and polypeptides, presenting a good unique flavor. However, the high addition of complex would weaken the probiotic effect, reduce the decomposition efficiency of fat and protein, and also cause the cheese to turn yellow and reduce the sensory score. In the early stage of the maturation process, the sensory score was significantly improved due to the occurrence of proteolysis reaction and lipolysis reaction (P<0.05）, but too long maturation period would lead to accumulation of bitter peptides and other substances, forming bad flavors and affecting sensory quality. In general, curcumin-bovine serum albumin complex can improve the quality of yak milk cheese, and the best quality of yak milk cheese is obtained when the compound supplemental level is 4% and the maturation time is 60 d.