Mirsalami Seyed Mehrdad, Mirsalami Mahsa, Alihosseini Afshar, Ghodousian Amin
Department of Chemical Engineering, Faculty of Engineering, Islamic Azad University Central Tehran Branch, Tehran, Iran.
Faculty of Engineering Sciences, Raja University, Qazvin, Iran.
Heliyon. 2024 May 31;10(11):e32263. doi: 10.1016/j.heliyon.2024.e32263. eCollection 2024 Jun 15.
The division of rennet in cheesemaking is split between the curd and whey, influencing the taste and texture of aged cheeses. Our study aimed to examine how raising the protein concentration in reconstituted skim milk (up to 8.8 %) affects the distribution of calf rennet activity (RA) in rennet curds produced through two methods: renting only and renneting with glucono-δ-lactone (GDL) to achieve slow acidification. The distribution of rennet activity (RA) into curds increased as the concentration of skim milk rose, ranging from 8.6 % to 29.1 % without acidification, and from 6.5 % to 19.4 % when combined with slow acidification. This increase seemed to be related to the retention of moisture and protein. Surprisingly, the concentration of residual RA in the whey (measured in international milk clotting units, IMCU/mL) remained unaffected and remained consistent with the initial IMCU/mL of milk. This suggests that the division of RA between curd and whey is not influenced by the association of enzymes with caseins (CNs). Instead, it is possible that the strength of interactions between CNs themselves plays a significant role. These findings could be valuable for research focused on enhancing the cheese aging process.
在奶酪制作过程中，凝乳酶在凝乳和乳清之间的分配情况会影响陈年奶酪的风味和质地。我们的研究旨在探究提高重组脱脂牛奶中的蛋白质浓度（最高至8.8%）如何影响通过两种方法制作的凝乳酶凝乳中犊牛凝乳酶活性（RA）的分布：仅使用凝乳酶和使用葡萄糖酸 - δ - 内酯（GDL）进行凝乳以实现缓慢酸化。随着脱脂牛奶浓度的升高，凝乳酶活性（RA）在凝乳中的分布增加，在未酸化的情况下，范围为8.6%至29.1%，在与缓慢酸化相结合时，范围为6.5%至19.4%。这种增加似乎与水分和蛋白质的保留有关。令人惊讶的是，乳清中残留RA的浓度（以国际牛奶凝固单位IMCU/mL测量）保持不变，并且与牛奶最初的IMCU/mL一致。这表明凝乳酶在凝乳和乳清之间的分配不受酶与酪蛋白（CNs）结合的影响。相反，酪蛋白自身之间相互作用的强度可能起着重要作用。这些发现对于专注于改善奶酪陈化过程的研究可能具有重要价值。
