Protein breakdown bacteria (rotten)

It would seem, that the decomposition of cheesecake in ripened cheese is mainly due to typical bacteria splitting protein bodies into simpler compounds. This was also believed in the past. We know now, that if it were in fact, the cheeses would rot and become unusable. In fact, perhaps only a few species of this group of bacteria contribute at best to the maturation of cheeses. As far as is known, their activity in this direction is subordinate. On the other hand, lactic acid bacteria are mainly involved in the proper maturation of cheeses. Many of their varieties can break down not only milk sugar, but also protein. By creating an acidic environment in the cheeses, they protect them from rotting, which would cause putrefying bacteria. These hate lactic acid, probably exceptionally, when there is little of it. However, they thrive in a neutral or alkaline environment. Thus, typical protein breakdown bacteria are generally harmful in cheese making.
Bacteria decomposing cheesecake break it down into ever simpler compounds with the help of proteolytic enzymes: parakazeinę, albumoses, peptony, amino acids, and then with the help of other enzymes into even simpler compounds, with the formation of ammonia and other foul-smelling, sometimes even poisonous substances. Protein breakdown bacteria are called peptonizing, and also putrefactive, when decomposition is accompanied by a foul smell.
We meet aerobes and anaerobes here, mobile and immobile, without spores and with spores. Usually they are oblong in shape.
For putrefying aerobes, which are mobile and form spores, are hay and potato hazel in many varieties (Bacillus subtilis i mesentericus). Their viable cells die during cooking, but the spores are destroyed only by prolonged heating at 120 do 130 °C. Therefore, we often find them in pasteurized or insufficiently sterilized milk. Although their presence in milk cannot be completely prevented, at least their number should be reduced and their development conditions more difficult. That's what cooling milk leads to (the optimum of these bacteria is at 30 ° C), avoiding dust in the stable, cleanliness at all. A small number of these pests usually fight against lactic acid bacteria, for they cannot stand acid, but found itself in advantage, They curl the milk into lumps as if with a weak rennet and instead of sour, they initially make it bitter, then a bad taste.
Of the aerobic putrefactive bacteria, which do not form spores, it almost always happens in Bact milk. fluorescens. It lives in soil and water, from where it easily gets into milk through the vessels. It develops already at temperatures close to 0 ° C.
There is also a misfit here (Proteus Bact. vulgare) and some dye-producing bacteria in milk and milk products, e.g. Bact. synxanthum, Bact. erythrogenes i Bact. bizarre.
A dangerous pest in cheese making is Bacillus putrificus. It is club-shaped with an endospore at the thicker end. He is an anaerobic. In addition to milk sugar, it also breaks down protein. It can tolerate a high concentration of lactic acid. Thus, lactic acid bacteria cannot always suppress it in cheeses. It is found in small amounts in every milk, however, here it develops poorly against lactic acid bacteria. Most of it is found in spoiled concentrated feed, as in bran, cakes and in spoiled hay fodder.
That hazelnut, as well as many of the spoilage microorganisms mentioned previously, it is always accompanied by the lack of proper cleanliness, whether in the stable, or in a cheese dairy. You can meet him in rotting cloths, brushes, washings residues, left carelessly in dairy vessels. In order to avoid this, the ships should be scalded, dry and ventilate in the sun.

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