Yogurt is a kind of milk beverage with sweet and sour taste. It is a dairy product which takes milk as raw material, adds beneficial bacteria (starter) to pasteurized milk, ferments, and then cools and fills. Yogurt products on the market are mostly solidified, stirred and fruity, with various juices and jams.
The production process of yogurt can be summarized as batching, preheating, homogenization, sterilization, cooling, inoculation, (filling: for solidified yogurt), fermentation, cooling, (stirring: for stirred yogurt), packaging and post-ripening. Modified starch is added in the batching stage.
Yogurt is fermented from fresh milk and is rich in protein, calcium and vitamins. Especially for those who can't enjoy milk because of lactose intolerance, yogurt can be a good choice.
But many yoghurts are made into "desserts", which are filled with sugar and various processed fruits, and it is these "packages" that are used by merchants to disguise themselves as healthy foods. Therefore, it is best to choose ordinary yogurt when buying, and add some fruit when necessary.
Main factors affecting the quality of yogurt
1, raw milk mixed with water, lack of dry matter. When the moisture content reaches 15%, the yogurt clots float in whey.
2. The coagulation ability of raw milk is reduced, and yogurt clots are fragile or thin soup-like.
3. Using the milk injected with antibiotics to produce yogurt will make the yogurt not solidify and the emulsion is sweet.
4. The workshop environment and equipment are polluted by phage, which makes the fermentation process slow or even stop; The residual cleaning solution and disinfectant will also stop fermentation, making the clot brittle and the emulsion sweet.
5. Improper selection of strains or single strains, inappropriate fermentation temperature and insufficient fermentation time lead to insufficient flavor and fragrance of yogurt. The bacteria are impure or the production equipment and pipelines are polluted by gas-producing bacteria, which leads to bubbles and spicy taste in yogurt. If it is contaminated by yeast, it will taste bad.