成熟温度和时间对牦牛乳硬质干酪中生物活性肽的影响

Effect of ripening temperature and time on bioactive peptides in hard cheeses made by yak milk

以不同条件成熟的牦牛乳硬质干酪为研究对象,探究成熟温度和时间对牦牛乳硬质干酪中水溶性多肽的DPPH自由基清除能力、抑菌性以及抑制血管紧张素转换酶(ACE)活性的影响。结果表明,5℃、10℃、15℃成熟4~6个月牦牛乳硬质干酪的水溶性多肽对DPPH自由基均有清除能力。5℃、10℃成熟5个月、15℃成熟4个月牦牛乳硬质干酪的水溶性多肽对DPPH自由基清除率最高,分别为(20.38±1.20)%、(28.70±0.67)%和(30.19±0.32)%。5℃、10℃、15℃成熟的牦牛乳硬质干酪在4~6个月成熟过程中,其水溶性多肽对大肠杆菌、金黄色葡萄球菌的抑制程度分别呈增强趋势。成熟温度从5℃提高到15℃时,牦牛乳硬质干酪的水溶性多肽对大肠杆菌、金黄色葡萄球菌和血管紧张素转换酶的抑制作用呈加强趋势。

Taking hard cheese made by yak milk ripened at different conditions as research objects,the effect of the ripening temperature and time on DPPH radical scavenging capacity,antibacterial activity and angiotensin converting enzyme (ACE) inhibitory activity of water-soluble peptides in hard cheeses made by yak milk was investigated. The results indicated that water-soluble peptides of cheese ripened at 5 ℃,10 ℃ and 15 ℃ for 4-6 months all exhibited DPPH radical scavenging activity. The DPPH radical scavenging rate of water-soluble peptides of the cheese ripened at 5 ℃ and 10 ℃ for 4 months,15 ℃ for 5 months reached the highest,which were (20.38±1.20)%,(28.70±0.67)%,and (30.19±0.32)%,respectively. The antimicrobial activity of water-soluble peptides of the cheese ripened at 5 ℃,10 ℃ and 15 ℃ against Escherichia coli and Staphylococcus aureus increased gradually from the fourth to the sixth month of ripening. With the ripening temperature increase from 5 ℃ to 15 ℃,the antimicrobial activity and ACE inhibitory activity of soluble peptides also increased.