Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin 150030, China.
Key Laboratory of Dairy Science, College of Food Science, Northeast Agricultural University, Harbin 150030, China; Inner Mongolia Yili Group Co. Ltd., Hohhot 010080, China.
J Dairy Sci. 2022 Sep;105(9):7322-7333. doi: 10.3168/jds.2021-21709. Epub 2022 Aug 6.
Yogurt, a traditional fermented dairy product, is made with a starter that contains Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus. The aim of this study was to investigate the effects of different concentrations of epigallocatechin gallate (EGCG; 0, 0.5, 1.0, 3.0, and 5.0 mg/mL) on the growth, metabolism, and acid production of lactic acid bacteria, as well as the texture, stability, and antioxidant activity of fermented milk (yogurt). The results showed that a low concentration of EGCG had no significant effect on the acid production capacity of the starter or on the water-holding capacity of the yogurt but did increase its viscosity. A high concentration (5.0 mg/mL) of EGCG delayed the acid production rate of the starter and decreased the water-holding capacity, but significantly increased the antioxidant activity of yogurt. The addition of EGCG significantly increased the hardness of yogurt. Therefore, EGCG can improve the texture of fermented milk and enhance its antioxidant activity and stability, thus improving the overall quality of yogurt.
酸奶是一种传统的发酵乳制品，由含有嗜热链球菌和德氏乳杆菌保加利亚亚种的发酵剂制成。本研究旨在探讨表没食子儿茶素没食子酸酯（EGCG；0、0.5、1.0、3.0 和 5.0mg/mL）对乳酸菌生长、代谢和产酸以及发酵乳（酸奶）的质地、稳定性和抗氧化活性的影响。结果表明，低浓度的 EGCG 对发酵剂的产酸能力或酸奶的持水能力没有显著影响，但会增加其黏度。高浓度（5.0mg/mL）的 EGCG 会延迟发酵剂的产酸速率并降低持水能力，但会显著提高酸奶的抗氧化活性。添加 EGCG 会显著增加酸奶的硬度。因此，EGCG 可以改善发酵乳的质地，并增强其抗氧化活性和稳定性，从而提高酸奶的整体质量。
