the Hygienic characteristic of canned food, preservov and concentrates
As Canned food is called the foodstuff prepared by various methods of conservation (physical, chemical) for the purpose of increase of their stability to storage. Depending on methods of conservation they share on canned food and preservy. Canned food receive by sterilisation of the foodstuff concluded in tightly corked container. All are thus destroyed vegetative and some not pathogenic sporoobrazujushchie forms of microorganisms. Preservy are the foodstuff tightly corked in special container, but not podvergshiesja sterilisations. Therefore they are not subject to long storage.
Quality of canned food and preservov depends, mainly, on quality of initial raw materials. The above sterilising effect less than microorganisms in a product which is subject to conservation, the.
Temperature conditions of storage preservov and canned food are a little various: preservy it is necessary to store at the temperature which is not exceeding 1-2 °; canned food - at 3 5 °s. The Period of storage of vegetable canned food, and also fishes in a tomato sauce is limited 1 year. Dairy preservy (milk condensed,) it is not recommended to store cocoa more than two years.
The Great value has the maintenance in canned food of salts of heavy metals as they can serve in the raised quantities as the reason of food poisonings. The quantity of lead in ware of cans should not exceed 0,04%, other impurity - 0,14%.
The Basic condition of long storage of tinned products is their full hermetic sealing and correct sterilisation. At a wrong mode of sterilisation the part of microorganisms remains viable and is the reason of occurrence biological the bomb-zha. This kind bombazha very dangerous as at the expense of remained viable microorganisms the product decays with formation of the gases which are sticking out a bottom and a cover banks. Such products are liable to destruction.
Chemical bombazh canned food it is caused by the hydrogen formed owing to corrosion poludy by which the internal surface metal banks becomes covered. Canned food with chemical bombazhem in the sanitary relation are not dangerous and can be supposed in food only after laboratory research on microflora presence. If canned food are stored at low temperature, contents banok can freeze and cause their swelling. This swelling can be observed and at overflow banks by a tinned product. Such swelling name physical bombazhem. In the absence of signs of damage the products which are in canned food with physical bombazhem, are supposed in food.
Happens also false bombazh (clapping bottoms) which occurs at wrong zakatke covers of a can and is not a damage indicator.
In preservah, preserved by salt and the acetic acid, the remained microorganisms and enzymes can at adverse temperature cause bombazh. Such preservy also are exposed to laboratory research and in the absence of pathogenic microflora are supposed in food.
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