Optimizing Milk Quality and Shelf Life: Investigating Refrigeration Effects on Fatty Acid and Protein Profiles

Understanding the changes that occur in milk during refrigeration is essential for optimizing dairy product processes and ensuring their quality and shelf life. In this study, we aimed to investigate the effects of a 7-day refrigeration period on the fatty acid (FA) profile and protein composition of milk. Our findings revealed significant alterations in the milk's FA profile after 7 days of refrigeration. There was a considerable decline of 47% in the variety of original FAs, accompanied by a 12.5% reduction in the total FA content. Interestingly, decanoic acid demonstrated remarkable stability, and its presence strongly correlated with the duration of storage, suggesting its potential as a reliable indicator for monitoring milk freshness. Regarding the protein composition, notable quantitative changes were observed in whey proteins following 7 days of refrigeration, while the content of essential nutrients remained relatively steady. Analysis indicated approximately 40% losses in proteins, such as beta-lactoglobulin (beta-LG), alpha-lactalbumin (alpha-LA), bovine serum albumin (BSA), lactoferrin, and kappa-casein. These losses could be attributed to the activity of psychrotrophic bacteria, producing proteinases. The results highlight that refrigeration significantly affects the composition and stability of milk's fatty acids and proteins. These findings contribute to our understanding of milk's sensorial and nutritional properties, providing insights for optimizing dairy product processes to ensure improved quality and extended shelf life. Further research is warranted to explore strategies for mitigating the impact of refrigeration on the fatty acid and protein profiles of milk. By implementing such strategies, we can enhance the nutritional value and organoleptic characteristics of refrigerated milk, ensuring its optimal quality for consumers.