Consiglio per la Ricerca in Agricoltura e L'analisi Dell'economia Agraria (CREA), Centro di Ricerca Zootecnia e Acquacoltura, Via Salaria, 31, 00015 Monterotondo (RM), Italy.
Molecules. 2021 Mar 5;26(5):1405. doi: 10.3390/molecules26051405.
Milk and dairy products can have variable contents of antioxidant compounds that contribute to counteract the oxidation of lipids and proteins during processing and storage. The content of active antioxidant compounds is closely linked to their protection by oxidation. Freezing is one of the factors that can reduce antioxidant activity. Freezing of milk or curd is frequently used in case of the seasonality of milk production and/or seasonal increased demand for some products. In this paper, the effect of using frozen curd on the oxidative stability of buffalo Mozzarella cheese was evaluated. Samples of buffalo Mozzarella with different frozen curd content (0%, 5%, 20%, and 50%) were produced and analyzed at one and nine days. Mozzarella cheese with higher frozen curd content had a significant increase in redox potential parallel to the decrease in antioxidant activity, showing less protection from oxidation. Lipid and protein oxidation, expressed respectively by malondialdehyde and carbonyl content, increased significantly with increasing frozen curd. At nine days, carbonyls significantly increased while malondialdehyde content did not vary, showing that during storage, fat was more protected from oxidation than protein. The average carbonyl levels were comparable to those of some cooked cheeses, and the malondialdehyde levels were even lower. The results of this study stimulate the investigation of new strategies to decrease the oxidative damage in cheeses produced in the presence of factors decreasing oxidative stability.
牛奶和乳制品的抗氧化化合物含量可能会有所不同，这些化合物有助于在加工和储存过程中抵抗脂质和蛋白质的氧化。活性抗氧化化合物的含量与其氧化保护密切相关。冷冻是降低抗氧化活性的因素之一。牛奶或凝乳的冷冻通常用于牛奶生产的季节性和/或某些产品季节性需求增加的情况。本文评估了使用冷冻凝乳对水牛乳 Mozzarella 奶酪氧化稳定性的影响。生产并分析了不同冷冻凝乳含量（0%、5%、20%和 50%）的水牛乳 Mozzarella 奶酪样品，分别在第 1 天和第 9 天进行分析。随着冷冻凝乳含量的增加，Mozzarella 奶酪的氧化还原电位显著增加，抗氧化活性相应降低，表明其抗氧化保护作用降低。脂质和蛋白质氧化分别用丙二醛和羰基含量表示，随着冷冻凝乳含量的增加而显著增加。在第 9 天，羰基含量显著增加，而丙二醛含量没有变化，表明在储存过程中，脂肪比蛋白质更能抵抗氧化。平均羰基水平与一些熟奶酪相当，丙二醛水平甚至更低。这项研究的结果促使我们研究新的策略，以降低在降低氧化稳定性的因素存在下生产的奶酪中的氧化损伤。
