Possible pollution in food processing includes:
Pyrolysis products
When the temperature of food processing is too high, some substances harmful to human body will be produced. For example, when the heating temperature of protein and oil is too high, its components will deteriorate through chemical action, and the substances produced by deterioration may be toxic or carcinogenic, which is harmful to human body after eating.
Benzopyrene pollution
This chemical substance is mainly produced by incomplete combustion of various organic substances (such as coal, diesel, gasoline, crude oil and cigarettes). Benzo (a) pyrene produced by incomplete combustion of fuel will directly contact with food during food production, causing pollution. It is reported that B(a)P in smoke and air falls into soil and water, from which plants can absorb B(a)P to form secondary pollutants of food. In addition, food is sometimes contaminated by substances containing B(a)P during processing and storage. If milk is stored in a container coated with paraffin, all B(a)P in paraffin can be transferred to milk.
The main measures to prevent B(a)P pollution are that the oil temperature should not exceed 170℃ during food processing, and the food can be smoked by electric furnace and indirect heating, so that the food does not directly contact with charcoal fire.
Nitrosamine pollution
There are many kinds of N- nitroso compounds, and the toxicity of different kinds of N- nitroso compounds is very different, and its acute toxicity mainly causes liver damage. Chronic toxicity is mainly carcinogenic.
The crude salt used in pickling vegetables contains nitrate, which can be reduced to nitrite by bacteria. At the same time, protein can be decomposed into various amines to synthesize nitrosamines. When food additive nitrite or nitrate is directly added to fish as a chromogenic agent, nitrosamines can also be formed under appropriate conditions. The main measure to prevent nitrosamines from polluting food is to improve food processing methods. If wood is smoked without fuel, it is best not to use or use less nitrate when processing pickled meat or fish food.
China stipulates that the N- nitrosamine in sausage, ham, bacon, bacon and other meat products (GB9677-88) and beer (GB2758-8 1) should not exceed 3μg/kg.
Pollution of harmful substances such as lead and arsenic.
When processing metal machinery and containers, it will lead to the migration of metal poisons, and the use of packaging materials that do not meet the hygiene requirements will also lead to the dissolution and migration of harmful substances. In addition, the use of food additives and unreasonable use of chemical cleaning agents will also cause food pollution by harmful metals such as lead and arsenic.
Biological pollution such as microorganisms and viruses.
Whether raw or cooked, dirty containers, dirty hands of employees, dust in the air, equipment not disinfected or not completely disinfected, packaging materials not disinfected or not completely disinfected, etc. Will cause microbial, virus and other biological pollution in food processing.