The shelf life is an important indicator that we often pay attention to when buying food, which tells us how long the food can maintain good quality and food safety. In the national standard GB 7718 National Food Safety Standard Labeling of Prepackaged Food, the definition of shelf life is the period during which the prepackaged food maintains its quality under the storage conditions specified on the label.
This "maintaining quality" has two meanings, one is the "safe to eat period", that is, the food will not cause harm to health during the shelf life. The other is the "best before taste", that is, the ability of food to maintain its quality characteristics such as appearance, smell, texture, and taste when properly stored.
It is important to note that the expiration date does not mean that the food has completely spoiled and is inedible. The fact that the merchant does not promise the quality of the food when marking the expiration date of the food does not mean that the food will spoil immediately after the expiration date. On the contrary, the final consumption date of the food should refer to the "shelf life", that is, the actual shelf life of the food under normal storage conditions.
The actual shelf life is not only affected by the storage conditions, but also depends on the packaging material of the food. Generally speaking, it is not recommended to eat foods with a short shelf life and easy spoilage, such as fresh milk, bread and bakery, vegetable juices, etc., beyond the expiration date. For some foods with a long shelf life, such as canned food, dry goods, etc., you can continue to observe the color and aroma of the food after the expiration date, and make sure that there is no significant change before deciding whether to eat it.
For example, milk on the market usually has a way back when setting the expiration date, which means that the actual expiration date may be longer than the labeled expiration date, which means that even if the milk has reached the expiration date, it can still be safely eaten as long as it has not spoiled according to the senses.
If the milk that has passed its expiration date has passed for a few days or even longer, even if it has not deteriorated, the nutritional value in it has been greatly reduced, and it is better not to eat it anymore so as not to have an impact on your health. Expired milk can breed bacteria, and when the number of bacteria reaches a certain level, it can cause harm to the human body;In addition, the nutrients such as protein in expired milk have also been destroyed, and continuing to drink such milk may cause problems such as diarrhea.
I forgot to drink the milk I bought at home, and when I remembered it, I found that it had expired. I can't drink it, but it's a pity to throw it away. Well, we can try some waste utilization methods to make the most of this expired milk.
1.Expired sour milk contains lactic acid, which has a good decontamination effect. Mixing milk and water in a 1:2 ratio and wiping the floor with a towel dipped in the mixture will protect the floor and make it shine as new. This wipe is chemical-free and very natural.
2.Dip the milk, gently rub the ink, the ink dissolves in the expired milk, and then wash it with detergent. In the same way, milk is also suitable for caring for leather goods. Mix milk and water, wipe the skin with a rag dipped in liquid, and wipe dry with a dry cloth to remove dirt and prevent the skin from drying out. Therefore, expired milk can be used not only to wipe wooden floors, but also to wipe leather products such as sofas and shoes, which can make cracks and wear more novel.
3.Soaking the oxidized silver jewelry in expired milk for 30 minutes and then brushing it gently with a toothbrush can remove rust and remove stains from the silverware. For those silverware that have rust spots and stains, you can soak them in expired milk to help remove the stains. After soaking for a certain amount of time, rinse off with detergent. If there is no expired milk, you can add some vinegar to the milk to soak it.
4.A small amount of rotted milk is poured into a small pit in the soil and the soil is buried. Used once a month, it provides nutrients to the plants.
5.For some farmers, adulteration of expired milk directly into the animal's feed is a good option. The vitamins and nutrients in milk can make animals such as cattle and sheep more robust, improving their growth and meat quality.
Even though milk is too old to drink, we can use it creatively to turn it into treasure. In daily life, we need to keep an eye on the shelf life of food and store food strictly according to storage conditions to ensure the safety and quality of food. By making the rational use of expired milk, we not only reduce waste, but also contribute to the environment.
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