Answer: Once you have purchased milk and refrigerated it promptly, it should retain its fresh taste for one to five days beyond the “sell-by” date if kept at the proper temperature. If it spoils before the date expires, this indicates it was not handled properly, and it should be returned to the store for a refund.
Step-by-step explanation:
fresh from the cow typically has a pH between 6.5 and 6.7. The pH of milk changes over time. As milk goes sour, it becomes more acidic and the pH gets lower. This occurs as bacteria in milk convert the sugar lactose into lactic acid.
