How can expired milk be so destructive?
Of course, this box of milk is not only expired, but also has not been stored in the refrigerator. It has been left outside for several days, and as a result, the food has become "drugs". In addition, the news of poisoning caused by eating expired food during this period is endless:
It looks terrible, doesn't it? In this series of food poisoning incidents, the culprit points to the same "murderer"-spoiled food!
Causes of food deterioration
Food is composed of carbohydrate, fat and protein, which is a source of energy for us and a delicious meal for bacteria and fungi. However, bacteria and fungi have more amazing metabolism and reproduction speed than humans. Once the food is placed at room temperature, the bacteria and fungi on it begin to increase exponentially, and the nutrients in the food begin to be decomposed. Bacteria and fungi will also produce toxins while growing, such as 1 carcinogen "aflatoxin" and so on.
The second reason is that food itself contains enzymes, and under the action of enzymes, the nutrients of food are broken down into a variety of low-grade products.
In addition, the physical and chemical conditions for storing food, the containers for holding food, the packaging of food and other factors will accelerate or directly lead to the deterioration of food.
The consequences of eating bad food
Take milk for example, milk is very nutritious and deeply loved by bacteria and fungi, so milk is also a breeding ground for bacteria and fungi.
Drinking spoiled milk can cause stomach, vomiting, abdominal pain, dizziness, sepsis and even life-threatening. The elderly and children have weak resistance and weak gastrointestinal digestion, and the consequences will be very serious if they are slightly careless.
In fact, most mothers know to give their babies fresh food, but it is inevitable that food needs to be preserved, such as taking the baby out for a trip, going out for a picnic, or cooking more food at one time and needing to be preserved in batches. At this time, you need to know some ways to keep food fresh. Of course, the preservation methods are different for different foods.
breast milk
Generally speaking, breast milk is not easy to deteriorate, because it contains many antibacterial ingredients. However, if the mother is milking, it is still necessary to pay attention to cleaning and disinfecting related utensils, and to master the method of preserving breast milk to ensure the food safety of the baby's rations.
Freshly squeezed breast milk is packed in clean bottles, and if there is a refrigerator, it is best to put it in the refrigerator.
The storage of breast milk needs to be stricter for sick and premature babies than for healthy babies fed at home. The evidence obtained from literature review shows that breast milk can be fed for 96 hours at the longest time in a clean environment and stored in a refrigerator at 0-4 degrees Celsius (evidence level C). It should be noted that the storage time of breast milk is different under different conditions, and this time can only be used as a reference.
When freezing breast milk, leave some space at the top of the container (it will expand after freezing).
Freeze a small amount of breast milk each time to avoid waste, for example, 50 ml each time.
The Society of Breastfeeding Medicine has instructions on how to store breast milk at home: breast milk can be packed in glass or plastic containers, including sealable plastic bags. The newly squeezed breast milk should be put in a clean container and then put in the refrigerator for refrigeration or freezing, and should not be added to the breast milk previously stored in the refrigerator.
How to store breast milk at home;
Wash hands thoroughly with soap/soap. Wash hands should be dried with clean towels or disposable paper towels, or dried with blowing air;
The extruded milk should be stored in the refrigerator for refrigeration or freezing;
Try to drink fresh milk if possible;
If you don't drink it within two days, freeze the breast milk;
Label each breast milk with a date and time, and drink the milk first.
(Source: WHO and Barker1987)
Thawing and heating of breast milk;
You can thaw breast milk overnight in the refrigerator.
Frozen milk should be thawed as soon as possible, but it should not be thawed with boiling water or at room temperature. You can gently shake the breast milk in warm water (not too hot) until it thaws. You can also wash it with cold water first, then slowly turn it into hot water until the frozen milk thaws, and then take the hot water bath in the container to the body temperature. You can also use a milk warmer to heat breast milk;
If the baby doesn't finish drinking, don't heat it again, so don't heat it too much every time;
Thawed but unheated milk can be stored in the refrigerator for 24 hours;
Milk thawed but not put in the refrigerator needs to be drunk within 4 hours; The breast milk in the milk warmer also needs to be drunk or dumped within 4 hours;
Do not freeze repeatedly;
If breast milk is left standing, the fat will separate and float on the surface. Shake gently to mix well.
milk powder
I often see people complaining about buying fake milk powder, such as bugs or lumps in it. In fact, it is possible that milk powder is not fake, but the result of improper storage of milk powder due to logistics and transportation, because milk powder is like human beings living in a candy hut to bacteria and viruses, and it is really easy to deteriorate!
Usually, formula milk needs to be eaten within one month after opening, and at the same time, three don 'ts should be done:
1, never put it in the refrigerator:
Both overheating and low temperature may affect the nutrition of formula milk, so it is best to put formula milk in a cool, dry and ventilated environment. The optimum temperature range is 13 to 24 degrees (at least 0 to 32 degrees).
2. Never put it in an old jar:
Old cans are easy to have milk powder residue, which will pollute the newly introduced formula milk or milk powder. I really think milk powder cans can be used to store items, and don't put new bags of milk powder.
3, don't flush the milk to feed the baby and then cover the lid:
This may be a subconscious habit. The baby is crying with hunger, and she is bent on rushing to feed the milk, and it is easy to forget to change the milk powder cover. Milk powder is easy to deteriorate, so it is necessary to reduce the chances of milk powder contacting the air or insects and foreign bodies entering. Please get into the good habit of covering the milk powder with a spoon.
If the formula is prepared in advance, put it in the refrigerator for no more than 24 hours; If it is placed at room temperature, it should not exceed 1 hour; If there is any formula that the baby has not finished drinking at one time, it is best to dump it, and don't leave it for a while. ?
milk
Milk is divided into pasteurized milk and normal temperature milk.
Pasteurized milk adopts mild sterilization temperature, which can kill most harmful microorganisms and almost completely preserve the nutritional components and flavor and taste, but it needs to be continuously refrigerated at low temperature, and the shelf life is only 3-7 days. Check the shelf life before drinking.
Pasteurized milk may go bad if it is left at room temperature for 2 or 3 hours. When it is hot, you must remember to take the milk in time and put it in the refrigerator in time. If you are shopping in a supermarket, you can also buy other things first, and then put the pasteurized milk in the shopping cart before checking out.
Normal temperature milk is milk sterilized by ultra-high temperature, and its shelf life is relatively long. Besides drinking it within the shelf life, you should also pay attention to:
Don't expose the milk to sunlight or light. Sunlight and light will destroy several vitamins in milk, and at the same time, it will lose its fragrance.
Pour milk into cups, teapots and other containers. If it is not finished, cover it and put it back in the refrigerator for refrigeration. Do not pour it back into the original bottle.
Complementary food/cooked food
It is best to make and eat complementary food now, and throw it away if you can't finish eating it. If you want to take it out, you should pay attention to the preservation method. The following knowledge point is very important:
4-60 degrees is the most suitable temperature for bacteria growth, also known as dangerous temperature. Therefore, when preserving food, what we have to do is to avoid dangerous temperatures as much as possible, so that those who are hot are always hot and those who are cold are always cold.
Before eating, it is best to keep hot food above 60 degrees and cold food below 4.4 degrees.
Do not store perishable food at room temperature for more than 2 hours (put it in the refrigerator within 2 hours! ), if the room temperature exceeds 32 degrees, don't let it exceed 1 hour.
The refrigeration temperature of the refrigerator should be set below 4 degrees, and the freezing temperature should be set below-18 degrees.
At home, too, many families are used to waiting for the food to cool before putting it in the refrigerator. In fact, this practice is not good. After eating, it should be sealed in time and put in the refrigerator. Putting it outside for a while will breed more bacteria.
According to the suggestion given by the Hong Kong Food Safety and Health Department to prepare food containing vegetables for infants over 6 months old:
The puree prepared for babies should be eaten immediately, and it is best not to store it.
If it must be stored, it can only be eaten for the next meal (less than 12 hours) and should be put in the refrigerator (below 4 degrees Celsius).
If it needs to be stored for more than 12 hours, it should be stored in a freezer (minus 18 degrees or below).
If it is not cooked immediately, fresh leafy vegetables should be stored in the refrigerator.