Department of Food Hygiene and Technology, Faculty of Veterinary Science, University of León, 24071, León, Spain.
Instituto de Productos Lácteos de Asturias (IPLA-CSIC), 33300, Villaviciosa, Asturias, Spain.
J Dairy Sci. 2021 Mar;104(3):2539-2552. doi: 10.3168/jds.2020-19036. Epub 2021 Jan 15.
The aim of this research was to study changes in the microbial populations, free AA profile, biogenic amine content, and sensory characteristics of ripened cheeses (100 and 180 d) produced in different seasons (summer, autumn, winter, and spring) from pasteurized sheep milk from 8 commercial flocks fed hay or silage diets. Twenty-one individual AA and 6 biogenic amines were determined by ultra-high performance liquid chromatography. Type of conserved forage for sheep feeding did not affect the variables studied, which is of great interest because hay and silage are low-cost ingredients for sheep feeding. Proteolysis led total free AA concentrations ranging between 35,179.26 and 138,063.71 mg/kg of cheese at 180 d of ripening. γ-Aminobutyric acid, which has been associated with beneficial effects on human health, was the second most abundant AA in all cheese samples, accounting for 15% of total free AA. Spring cheeses showed 2-fold higher concentrations of γ-aminobutyric acid than summer and autumn cheeses at the end of ripening. Overall, spring, winter, and autumn cheeses had lower average concentration of biogenic amines (431.99 mg/kg of cheese) than summer cheeses (825.70 mg/kg of cheese) as well as better sensory characteristics. Therefore, this study could provide the dairy industry with useful information for producing cheeses with valuable nutritional and sensory quality for consumers.
本研究的目的是研究不同季节（夏季、秋季、冬季和春季）从巴氏杀菌绵羊奶中生产的成熟奶酪（100 和 180 天）中微生物种群、游离 AA 谱、生物胺含量和感官特性的变化，这些奶酪来自 8 个商业羊群，采用干草或青贮饲料喂养。通过超高效液相色谱法测定了 21 种个体 AA 和 6 种生物胺。绵羊饲料中保存的饲料类型并未影响研究中的变量，这非常有趣，因为干草和青贮饲料是绵羊饲养的低成本成分。在成熟 180 天时，蛋白质水解导致游离 AA 总浓度在 35,179.26 和 138,063.71 mg/kg 奶酪之间变化。γ-氨基丁酸与对人类健康的有益影响有关，是所有奶酪样品中第二丰富的 AA，占游离 AA 总量的 15%。在成熟末期，与夏季和秋季奶酪相比，春季奶酪中的γ-氨基丁酸浓度高 2 倍。总的来说，春季、冬季和秋季奶酪的生物胺平均浓度（431.99 mg/kg 奶酪）低于夏季奶酪（825.70 mg/kg 奶酪），感官特性也更好。因此，这项研究可以为乳制品行业提供有用的信息，以生产对消费者具有有价值的营养和感官品质的奶酪。
