为探究适宜的KCl替代NaCl代盐浓度组合,以A盐组合[0%(质量分数,下同)NaCl,0% KCl]为对照组,终盐质量分数为6%,采用不同代盐组合(B:6% NaCl,0% KCl;C:3% NaCl,3% KCl;D:0% NaCl,6% KCl)分别干预嗜酸乳杆菌和大肠杆菌,并在4个时间点(1 h、3、5和7 d)监测,采用菌落形成单位、流式细胞术和傅立叶变换红外光谱研究KCl替代NaCl对嗜酸乳杆菌和大肠杆菌的活菌数、酯酶活性、膜完整性和细胞结构的影响。结果表明:在6%终盐质量分数下,C盐(3% NaCl,3% KCl)组合在不显著影响嗜酸乳杆菌的情况下可抑制大肠杆菌生长并破坏其细胞结构。因此,KCl部分替代NaCl可减少钠盐摄入,且在不影响益生菌生长的情况下抑制致病菌的生长,为提高食品质量与安全提供实验依据。
To find suitable concentration of KCl as the substitute for NaCl for inhibiting the growth of Escherichia coli without affecting the growth of Lactobacillus acidophilus, different salt concentration combinations (A: 0% NaCl, 0% KCl; B: 6% NaCl, 0% KCl; C: 3% NaCl, 3% KCl; D: 0% NaCl, 6% KCl) were used. The effects on cell viability, esterase activity, membrane integrity and cell structure of L. acidophilus and E. coli were examined. The results showed at 6% final salt concentration, the combinations of C-salt (3% NaCl, 3% KCl) could significantly affect cell viability and cell structure of E. coli without affecting L. acidophilus. It is indicated that with an appropriate concentration ratio, KCl could partially replace NaCl to reduce sodium intake, and inhibit pathogen without affecting the growth of probiotics, which that provides experimental basis for improving food quality and safety.
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