How long can unopened fresh milk be kept at room temperature?

Unopened fresh milk is one of the main drinks in people's daily diet, but many people don't know the storage time of unopened fresh milk at room temperature, and there are even misunderstandings. In fact, the storage time of unopened fresh milk at room temperature is limited, so it is necessary to pay attention to the corresponding storage measures to ensure the quality and safety of milk.

Precautions for storage of unopened fresh milk at room temperature For unopened fresh milk, the following points should be paid attention to during storage at room temperature:

Storage environment: ventilated, low temperature (5-20℃), dry and dark storage time: unopened fresh milk can be stored at room temperature for 2-4 hours under the above environmental conditions. Preservation method: When preserving unopened milk, it is recommended to put it in a clean, covered and odorless container to avoid exposure to air. Principle of normal temperature storage of unopened fresh milk The normal temperature storage time of unopened fresh milk is affected by microorganisms and temperature, which is from a microscopic point of view.

From the microscopic point of view, fresh milk contains a small amount of bacteria, including some probiotics, which will not have a negative impact on milk, but also provide nutrition and health care for the human body. When milk can't be preserved, it will lose its fresh flavor due to the function of deoxyacidification enzyme (LOX). At the same time, a variety of bacteria began to multiply in milk, among which acid-producing bacteria were the main ones, which could reduce the pH value of milk and increase the acidity of milk, thus leading to the deterioration of milk.

Therefore, in order to prolong the storage time of fresh milk at room temperature, it is necessary to control the reproduction and growth of bacteria by controlling the temperature and maintaining air circulation.

Factors affecting the storage time at room temperature The storage time of unopened fresh milk at room temperature is affected by the following factors:

Temperature: The higher the temperature, the faster the bacteria multiply and the shorter the shelf life of milk. Air: impurities and bacteria in the air will accelerate the deterioration of milk, so keep the air circulating and free from odor. Container: The container for storing milk needs to be dry, odorless, sealed and protected from light, so as to inhibit the reproduction of bacteria to the greatest extent. Raw materials: the quality, formula and processing technology of fresh milk will also have a certain impact on the storage time at room temperature. Although the storage time of unopened fresh milk at room temperature is limited, reasonable storage measures can prolong the shelf life of milk and ensure its quality and safety. Therefore, we suggest that when buying fresh milk, we should choose products with good quality, long validity and good packaging to avoid buying expired, damaged or smelly milk. Moreover, milk should be stored in the refrigerator as soon as possible after purchase, and eaten immediately after opening, so as to avoid the deterioration of milk caused by excessive storage.