操作方法:
目前國際上通用的巴氏高溫消毒法主要有兩種：一種是將牛奶加熱到62℃-65℃，保持30min。采用這一方法，可殺死牛奶中各種生長型致病菌，滅菌效率可達(dá)97.3%-99.9%，經(jīng)消毒后殘留的只是部分嗜熱菌及耐熱性菌以及芽孢等，但這些細(xì)菌多數(shù)是乳酸菌，乳酸菌不但對(duì)人無害反而有益健康；另一種方法將牛奶加熱到75℃-90℃，保溫15s-16s，其殺菌時(shí)間更短，工作效率更高。但殺菌的基本原則是，能將病原菌殺死即可，溫度太高反而會(huì)有較多的營養(yǎng)損失 。
主要應(yīng)用:
巴氏滅菌法主要為牛奶的一種滅菌法，既可殺死對(duì)健康有害的病原菌又可使乳質(zhì)盡量少發(fā)生變化。巴氏殺菌不可能殺死所有細(xì)菌，它只能將致病菌的數(shù)量降低到對(duì)消費(fèi)者不會(huì)造成危害的水平。巴氏滅菌法除牛奶之外，也可應(yīng)用于發(fā)酵產(chǎn)品
主要原理:
在一定溫度范圍內(nèi)，溫度越低，細(xì)菌繁殖越慢；溫度越高，繁殖越快。但溫度太高，細(xì)菌就會(huì)死亡。不同的細(xì)菌有不同的較適生長溫度和耐熱、耐冷能力。巴氏消毒其實(shí)就是利用病原體不是很耐熱的特點(diǎn)，用適當(dāng)?shù)臏囟群捅貢r(shí)間處理，將其全部殺滅。但經(jīng)巴氏消毒后，仍保留了小部分無害或有益、較耐熱的細(xì)菌或細(xì)菌芽孢，因此巴氏消毒牛奶要在4℃左右的溫度下保存，且只能保存3～10天，至多16天
Operation method:
At present, there are two kinds of pasteurization commonly used in the world: one is to heat the milk to 62 ℃ - 65 ℃ and keep it for 30min. This method can kill all kinds of growth type pathogenic bacteria in milk, and the sterilization efficiency can reach 97.3% - 99.9%. After disinfection, only a part of thermophilic bacteria, heat-resistant bacteria and spores are left, but most of these bacteria are lactic acid bacteria, which are not only harmless to people, but also beneficial to health; another method is to heat the milk to 75 ℃ - 90 ℃ for 15s-16s, which can shorten the sterilization time More efficient. But the basic principle of sterilization is that the pathogen can be killed, and if the temperature is too high, there will be more nutrition loss.
Main applications:
Pasteurization is mainly a sterilization method for milk, which can not only kill the pathogenic bacteria harmful to health, but also make the milk quality change as little as possible. Pasteurization cannot kill all bacteria, it can only reduce the number of pathogens to a level that will not cause harm to consumers. Besides milk, pasteurization can also be applied to fermented products
Main principle:
In a certain temperature range, the lower the temperature, the slower the bacterial reproduction; the higher the temperature, the faster the reproduction. But when the temperature is too high, the bacteria die. Different bacteria have different suitable growth temperature, heat and cold resistance. Pasteurization is actually the use of pathogens is not very heat-resistant characteristics, with appropriate temperature and heat preservation time treatment, all of them will be killed. However, after pasteurization, a small number of harmless or beneficial, relatively heat-resistant bacteria or bacterial spores are still retained. Therefore, pasteurized milk should be kept at a temperature of about 4 ℃, and can only be kept for 3-10 days, up to 16 days
