乳酸菌混菌发酵制备豆清液多肽动力学模型的建立

为探究乳酸菌混菌发酵豆清液制备多肽的动态过程及钙螯合活性变化,建立描述菌体生长、多肽生成及蛋白质消耗动力学模型,测定了发酵过程中的pH值、蛋白酶酶活和钙螯合活力。结果表明,动力学模型具有良好可靠性;乳酸菌混菌发酵过程中多肽含量在对数期达到5.31 mg/mL,pH值下降至3.5左右后稳定;酸性蛋白酶酶活在4～8 h较高,最大酶活为3.6 U/mL;钙螯合活力总趋势为先升高后降低,在14 h达到最高值33.35%。

Establishment of kinetics model of polypeptides preparation from soybean whey by mixed lactic acid bacteria fermentation

In order to explore the dynamic process of mixed lactic acid bacteria fermentation of soybean whey to produce polypeptides and the calcium chelating activity of polypeptides, the kinetic model was established to describe the growth of mixed bacteria fermentation cells, peptide production and protein consumption. The pH, protease activity, calcium chelation activity were determined during the fermentation process. The test results showed that the kinetic model had good reliability, the peptide content reached 5.31 mg/ml in the logarithmic phase during the fermentation process, and the pH value stabilized after dropping to about 3.5. The acid protease activity was higher at 4-8 h, and the maximum activity was 3.6 U/ml. The general trend of calcium chelation activity in the system was firstly increased and then decreased, the highest value was 33.35% at 14 h.