Good food category "food is too hot to put in the refrigerator, it will go bad!" " ""overnight food can't be eaten, there will be carcinogens! (Editor's recommendation: Yan Zonghai: Eating overnight dishes will not cause cancer! On the contrary, this matter is even more worrying. ) "eggs can't be put in the refrigerator door. It's easy to break when it's open or closed! I believe you have heard some myths about refrigerated refrigerators, but are they all true? This time, let me solve the misunderstanding of refrigerator refrigeration one by one, and hit it with one blow! * You must know the fat Tom principle. Before solving these myths, we should first talk about the fat Tom principle, which is the most understandable principle in the catering and food industries. Food: Food is a nutrient-rich substance, and it is also the favorite of microorganisms. ? Acidity: Acidity. Bacteria that can cause human diseases are called food harmful bacteria. The pH value of these food harmful bacteria is between 4.6 and 7.5, so the acidity can be adjusted to 4.5 (such as adding citric acid to drinks), which can avoid the growth of food harmful bacteria. ? Temperature: temperature, the growth range of harmful bacteria in food is between 5 and 60 degrees, and it will grow rapidly at 20 to 50 degrees. ? Time: Time, food needs to be heated to above 60 degrees or cooled to below 5 degrees in a short time after preparation to reduce the chances of bacterial growth. ? Oxygen: Food harmful bacteria are mostly aerobic bacteria, which are easy to grow in the presence of oxygen (except Botox). ? Moisture: Water activity refers to the proportion of water that bacteria can use in food. The higher the water activity, the easier it is for bacteria to grow. Designing the manufacturing process according to these principles can avoid the harm of many microorganisms, and then use the fat Tom principle to see the following myths! Good food "food is too hot to be put in the refrigerator, it will go bad!" """overnight food can't be eaten, there will be carcinogens! (Editor's recommendation: Yan Zonghai: Eating overnight dishes will not cause cancer! On the contrary, this matter is even more worrying. ) "eggs can't be put in the refrigerator door. It's easy to break when it's open or closed! I believe you have heard some myths about refrigerated refrigerators, but are they all true? This time, let me solve the misunderstanding of refrigerator refrigeration one by one, and hit it with one blow! * You must know the fat Tom principle. Before solving these myths, we should first talk about the fat Tom principle, which is the most understandable principle in the catering and food industries. Food: Food is a nutrient-rich substance, and it is also the favorite of microorganisms. ? Acidity: Acidity. Bacteria that can cause human diseases are called food harmful bacteria. The pH value of these food harmful bacteria is between 4.6 and 7.5, so the acidity can be adjusted to 4.5 (such as adding citric acid to drinks), which can avoid the growth of food harmful bacteria. ? Temperature: temperature, the growth range of harmful bacteria in food is between 5 and 60 degrees, and it will grow rapidly at 20 to 50 degrees. ? Time: Time, food needs to be heated to above 60 degrees or cooled to below 5 degrees in a short time after preparation to reduce the chances of bacterial growth. ? Oxygen: Food harmful bacteria are mostly aerobic bacteria, which are easy to grow in the presence of oxygen (except Botox). ? Moisture: Water activity refers to the proportion of water that bacteria can use in food. The higher the water activity, the easier it is for bacteria to grow. Designing the manufacturing process according to these principles can avoid the harm of many microorganisms, and then use the fat Tom principle to see the following myths! First, hot dishes are easily broken when frozen? "Hot dishes should be refrigerated, otherwise water vapor will condense after entering the refrigerator, increasing humidity and allowing bacteria to breed." No! You can directly ice it! In response to the first statement, I just want to answer which leftovers are not rich in water? So don't worry about whether it will cause water vapor condensation. The second statement is wrong, because the cooling process needs conduction, and the surface temperature drops, so that the low temperature "seeps into the interior". According to the "temperature" and "time" in the fat Tom principle, it is necessary to cool down to 4 degrees as soon as possible. This myth not only exists in Taiwan Province Province, but also is listed as one of the 10 big dangerous food myths by the American Food Safety Information Network. According to the suggestion of the US Food and Drug Administration, food should not be stored for more than two hours at room temperature, and it should not be stored for more than one hour at higher temperature. Therefore, it is right to freeze food as soon as possible and leave the dangerous temperature range where harmful bacteria grow in food. (Editor's recommendation: 12 kinds of foods that don't need refrigeration) Second, direct refrigeration of hot dishes will spoil other dishes? Freezing hot dishes directly will indeed destroy the cold room state of the refrigerator, increase the ambient temperature and increase the chances of bacteria breeding in the food in the refrigerator. But if you put the dish in cold and ice again, it may increase the risk of many bacteria doing harm to health. What should you do? In addition, will direct freezing of hot dishes lead to refrigerator failure? The cold storage of hot dishes leads to the operating burden of the refrigerator, which is related to whether the compressor of the refrigerator itself is strong enough, whether it is a fixed frequency or a variable frequency motor. Therefore, considering the above two factors, my suggestion is that hot dishes and soup can be cooled to about 60 degrees first, and even can withstand 50 degrees before entering the refrigerator quickly (this is the temperature at which fingers will feel "hot" but will not paste). ? * Because it is lower than 60 degrees or even 50 degrees, it will enter the stage of rapid growth of harmful bacteria in food. It is right to enter the refrigerator quickly and let the temperature drop to a temperature far away from the growth of harmful bacteria. Third, eggs and milk can't be put in the refrigerator door? Previously, it was thought that the temperature of refrigerator door was relatively high, and it was easy to lose temperature when opening and closing, so products with short shelf life such as eggs and milk could not be placed in the refrigerator door to avoid damage. But in fact, many refrigerators do internal cold circulation through air cooling, and some refrigerators have measured the results. The temperature difference between the air outlet and the refrigerator door is only about 0.5 degrees, so I don't think it will affect the freshness of the refrigerator door. Our focus should not be on the location of these foods in the refrigerator, but on avoiding long-term refrigeration. The fresher the food, the better. Besides, don't take too long to open the refrigerator to get things, which can reduce the chance of cold air escaping from the refrigerator. This is what we should pay attention to. (Editor's recommendation: Open the refrigerator and raise the temperature by 4℃! Tan Dunci 5 Refrigeration knowledge helps you keep fresh and save electricity) Fourth, are there many carcinogens in overnight dishes? It is rumored on the Internet that the nitrite content in overnight dishes is very high, and eating overnight dishes will cause cancer. Nitrate in vegetables will indeed greatly increase nitrite after the action of microorganisms, so the carcinogenic problem of overnight vegetables will return to whether nitrite itself will cause cancer. Nitrite itself does not cause cancer, but nitrite meets free secondary amine to form carcinogen nitrosamine. Nitrate and nitrite in vegetables are good and pose very low risk to human body. In addition, many studies have pointed out that nitric oxide formed after nitrite metabolism can relax the cardiovascular system, and when combined with specific fatty acids, it will form substances beneficial to the human body. Some studies even speculate that the Mediterranean diet can protect the cardiovascular system, and nitrite and nitrate also play a role. 5. Will the nutrition of overnight dishes be lost? The nutrition of overnight dishes may be really low, but what are nutrition and vitamins? Minerals or protein? I can't think of any reason to reduce it if it is based on three nutrients (carbohydrate, oil and protein) or minerals. ? But in terms of vitamins, vitamin C may be one of them. Studies in Lebanon found that the vitamin C content of "cooked" dishes was lower than that of "fresh" ingredients, and it was determined after one day of cold storage. The results show that the content of vitamin C is lower than that of "cooked" dishes, which means that vitamin C is lost not only during cooking, but also during refrigeration. (Editor's recommendation: Hot cauliflower loses 77% of its nutrients! 7 anti-cancer vegetables are cooked in this way, and the nutrition is completely preserved) * Vitamin C content: fresh > freshly cooked > refrigerated for one day > reheated in microwave oven. The online article says that other antioxidant nutrients, such as polyphenols, will be oxidized. But it doesn't seem to be an established thing in science, and there are too many nutrients with antioxidant effect, which is difficult to be confirmed by experiments, and there is little research on "leftovers", so I take the research on other ingredients as the representative. In 20 17, a study published in J Food Sci Techno carried out experiments on blueberries, and discussed the polyphenol content and antioxidant capacity of blueberries after being harvested and refrigerated for 14 days. Scholars have concluded that cold storage will not reduce the nutritional value of blueberries. However, another study found that cold storage can lead to the loss of polyphenols in red raspberries, which means that this study is actually different. In my opinion, diet does not depend entirely on leftovers. Usually, we also eat a lot of fresh fruits and vegetables, freshly cooked meals and so on. So we don't have to pay too much attention to whether the nutrition of leftovers is lost. The focus of overnight dishes is not to waste. If you want to avoid any "risks", you must accurately grasp the quantity and don't have any surplus. About the author: Lin Hao Food Class is a team of nutritionists and food technicians with backgrounds in food, clinic, consultation and health care products. In this era of information explosion, I want to share correct health information with you. Welcome to the fan page of Good Food Class. Let's pass on health knowledge and information to make our life more active and healthy. Special page for gourmet vermicelli