On food hygiene and safety issues

1. Hazard factors causing food poisoning

1. The food itself is harmful and toxic, such as poisonous weeds, mangroves, sprouted potatoes, cassava, bitter almonds, puffer fish, yellow croaker and poisonous mussels.

2. Food is polluted by harmful poisons, such as chemical poisons and harmful organisms.

3. Unsanitary equipment, containers or utensils.

4. Cross-contamination of raw and cooked foods.

5. Corrupt and deteriorated raw materials are used.

6. The leftover food has not been reheated.

7. Misuse of toxic and harmful substances.

8. improper storage.

9. Improper food processing and cooking.

1. Poor personal hygiene.

II. Classification of food poisoning

1. Microbial food poisoning

(1) Bacterial food poisoning is characterized by gastrointestinal symptoms, often accompanied by fever, and its incubation period is relatively large compared with chemical ones.

(2) Fungal toxins and fungal food poisoning, with characteristics: poisoning mainly occurs through food contaminated by fungi; The mycotoxin in food cannot be destroyed by heating treatment with general cooking methods; No infectivity and immunity, mycotoxins are generally small molecular chemicals, which do not produce antibodies to the body; Fungi need a certain temperature and humidity to grow, reproduce and produce toxins, so poisoning often has a clear seasonal and regional characteristics.

2, chemical food poisoning, characteristics: the onset is related to eating time and consumption; ; The onset is fast, the incubation period is short, mostly in minutes to hours; Often in groups, patients have the same clinical manifestations; Severe poisoning, long course of disease, high morbidity and mortality; The seasonality and regionality are not obvious, and the poisoned food has no specificity; Chemical poisons can be detected in samples such as leftover food, vomit, blood and urine. Eating toxic chemicals or food contaminated with toxic chemicals by mistake; The clinical manifestations are diversified due to different toxic substances, and are generally not accompanied by fever.

3. Foods prohibited from purchasing

1. Foods that are spoiled, rancid, moldy, insect-borne, unclean, mixed with foreign substances or have other abnormal properties, contain or are contaminated with toxic and harmful substances, and may be harmful to human health;

2. Meat and its products that have not passed the medical and health inspection or failed the inspection;

3. stereotyped packaged food that has expired or does not meet the requirements of food labeling;

4. Other foods that do not meet the food hygiene standards and requirements.

fourth, why do you say that leftovers should be thoroughly heated before eating?

All kinds of leftovers should be put in the refrigerator as soon as possible, and heated thoroughly when eating again. This is the best way to eliminate microorganisms. When storing leftovers, microorganisms may have grown and multiplied, because proper storage can only slow down the growth of microorganisms, but not kill them, so leftovers should be eaten as much as possible. Thorough heating means that the temperature of all parts of the food reaches at least 7℃. Usually, this can ensure the hygienic quality of food.

But it is best not to eat fresh vegetables overnight and every other meal. This is especially true for all kinds of leafy vegetables, such as Chinese cabbage, which contains a lot of nitrate. After a night, the non-toxic nitrate will be transformed into highly toxic nitrite due to the action of bacteria. Nitrite can oxidize low iron hemoglobin in human blood into methemoglobin, causing poisoning symptoms such as headache, dizziness, nausea, vomiting and palpitation. Nitrite is also a carcinogen.

5. Why are some bad hand habits potentially dangerous?

There are many small gestures in our hands that are unconsciously and often repeated. Such as wiping your nose, scratching your hair, scratching your beard, touching your mouth and scratching, if these actions are combined with cooking, there is a risk of mutual pollution. In history, there have been events that caused diseases to spread because of these actions. We should avoid these small moves when making food. If we find these moves, we should wash our hands immediately and don't be afraid of trouble. This is especially true in collective canteens, hotels, restaurants, etc. Developing good hygiene habits is one of the important links to prevent the epidemic of diseases and ensure the hygiene of eating.

VI. Why should we avoid direct contact with cooked food and other ready-to-eat foods with our hands

There are a lot of bacteria on our hands. Although they are washed before touching food, it is impossible to wash them all off. Cooked food and other ready-to-eat foods are mostly not heated. Once the bacteria are contaminated, the bacteria will enter the human body with these foods, causing food poisoning.

if you must handle food by hand, you should wear gloves (if the food is already wrapped or needs to be cooked, you don't need to wear gloves). Attention should be paid to the following requirements when wearing gloves:

1. When gloves are damaged, polluted or taken off for any reason, these gloves should be discarded.

2. Change gloves between handling raw and cooked food.

3. Always change gloves (at least once an hour).

4. gloves can't be used after use.

VII. Why can improper cooking methods produce various carcinogenic factors

In daily life, improper cooking methods can produce various carcinogenic factors.

1, animal meat, fish and other animal proteins, excessive heat, easy to produce carcinogen aminomethyl derivatives, so animal meat, fish, not stir-fried, not to eat after burning.

2. heating or frying food at high temperature can produce carcinogenic polycyclic aromatic hydrocarbons, so you should eat less or not eat fried food.

3. Fresh vegetables will produce carcinogen nitrite if left standing for too long after washing and cutting, so vegetables should be washed, cut, fried and eaten, which will not only avoid nitrite production, but also reduce the loss of nutrients, especially water-soluble vitamins.

4. It is forbidden to smoke food with fuels such as coal, crude oil and firewood, otherwise it will produce carcinogen 3.4 benzopyrene, which is harmful to human body.

VIII. Why food poisoning occurs

Food poisoning should first be poisoned food, and the food contains enough pathogenic factors. With these two items, food poisoning can be caused.

After analysis, there are ten common factors that cause food poisoning:

1. Improper refrigeration of food (insufficient refrigeration temperature);

2. Store food at room temperature (the room temperature is within the dangerous temperature zone);

3. Prepare food too early (so that bacteria have enough time to reproduce);

4. improperly cooling food (cooling time is too long);

5. Improper heating of food (incomplete heating or long-term heating at low temperature);

6. Poor housekeeping (accidental pollution accident);

7. Cross-contamination (imperfect health system and bad personal hygiene habits);

8. Inappropriate thawing of food (thawing at room temperature);

9. Food processors or producers are infected and have bad hygiene habits;

1. The processed food is contaminated.