The worldwide increase in cheese consumption combined with a scarcity of rennet as well as ethical concerns have resulted in a global interest for natural milk coagulants from plant sources. In this study, the influence of ginger protease in comparison to calf rennet on the physicochemical, microbiological, and sensory characteristics of Peshawari cheese manufactured from cow's milk was examined. For most of the physicochemical parameters (fat, protein, lactose, acidity, pH), and the main groups of microorganisms (total viable, enterobacteria, Lactobacilli, and molds and yeasts) investigated, no significant (P>0.05) differences were observed between the two cheeses made by using different coagulants. However, significantly lower (P<0.05) levels of moisture and higher levels of soluble nitrogen were observed in the cheese produced by ginger protease compared to that made using calf rennet. The main sensory attributes (appearance, body texture, and flavor) were significantly enhanced (P<0.05) in Peshawari cheese prepared with ginger protease. Importantly, no bitterness was noted by the sensory panel in the Peshawari cheese made with ginger protease. The results reveal that the ginger protease may have potential application for the manufacture of Peshawari cheese.
摘要-生姜蛋白酶作为凝乳剂促进 Peshawari 干酪蛋白质水解和改善感官质量世界范围内奶酪消费量不断增加,而传统凝乳剂小牛皱胃酶供应相对不足以及出于宗教方面 的考虑,使得一些植物来源的凝乳酶研究引起了广泛兴趣。本文以牛奶为原料,比较了生姜 蛋白酶和小牛皱胃酶作为凝乳剂制备的 Peshawari 奶酪在物化特性、微生物特性以及感官特 性方面的差异。结果表明,用两种凝乳酶制备的奶酪,其大部分的物化特性指标(脂肪、蛋 白质、乳糖、酸度、pH)以及主要的微生物指标(活菌总数、肠道菌、乳酸菌、真菌和酵 母)均无明显差异(P > 0.05)。但以生姜蛋白酶为凝乳剂制备的奶酪其含水量明显低于用 小牛皱胃酶生产的奶酪(P < 0.05),相反可溶性氮(SN)的含量前者却明显高于后者(P < 0.05) 。此外,结果还显示用生姜蛋白酶为凝乳剂制备 Peshawari 奶酪可以明显改善主要的 感官特性(外观、质构、风味)(P < 0.05),更重要的是,以这种方式生产的 Peshawari 奶 酪没有苦味。这一研究表明生姜蛋白酶作为植物来源的凝乳剂在 Peshawari 奶酪生产中具有 潜在应用价值。