Yogurt, buttermilk, kefir, sour cream – sour milk products are part of many people’s daily menu. And rightly so: buttermilk and co. not only taste really good, but are also healthy. Not only the protein and vitamins contribute to this, but also the lactic acid bacteria that are responsible for the sour taste. These lactic acid bacteria support the intestinal flora as probiotics.
Production of sour milk products
In the supermarket, you can almost get lost between the shelves, so many dairy products are offered. But what is behind the great variety? First of all, most sour milk products are made in a similar process, mainly from cow’s milk, but also from goat’s, sheep’s or soy milk. To obtain yogurt, certain lactic acid bacteria are added to the milk to utilize a portion of the milk. In the process, the lactose present in the milk is converted into lactic acid. This process coagulates the milk, which gives yogurt its fresh, tart taste and also makes it so digestible. By the way, the word “yogurt” comes from the Turkish “yoghurmak”, which means “to thicken”.
Clockwise and counterclockwise lactic acid
Lactic acid is usually present as a mixture of two forms, referred to as dextrorotatory or laevorotatory. Dextrorotatory L(+) lactic acid is also found in human metabolism and is therefore easily digested. It helps to produce energy in metabolism and protects the intestinal mucosa. The levorotatory D(-) lactic acid, on the other hand, is broken down more slowly – and is therefore not recommended for infants under twelve months of age and people with intestinal disorders. On products containing only the more digestible dextrorotatory form, this is declared on the package.
How are buttermilk, kefir and co. produced?
In addition to yogurt, there are other sour milk products, some of which are produced in a similar way:
- For the production of sour cream, sour cream and crème fraîche, the same process is used as for yogurt, but on the basis of cream. Depending on the fat content of the product, different amounts of water are removed from the cream. Thus, sour cream comes to at least 10, sour cream to at least 20 and crème fraîche to at least 30 percent fat.
- Buttermilk differs – just like kefir – in its production from the other sour milk products. Buttermilk is actually a waste product left over from the extraction of butter from sour cream. It contains similar nutrients as milk, but is much lower in fat.
- For the preparation of kefir, so-called kefir nodules – a mixture of yeasts and bacteria – are added to the milk. In addition to lactic acid, they also form small amounts of alcohol and carbonic acid. This is why kefir bubbles minimally. The product is easily digestible, contains many B vitamins and has a positive effect on intestinal activity. Because of these properties, kefir is also called the “drink of the centenarians”.
- Whey is a liquid that separates during the production of curd and cheese. Sweet whey is formed by thickening the milk with rennet (a calf stomach enzyme), especially in cheese production, sour whey in the coagulation processes caused by lactic acid bacteria (especially in the production of curd). Whey is very low in fat and calories and contains high-quality protein, especially B vitamins and minerals such as potassium and calcium.
Ingredients of sour milk products
Whether it’s buttermilk, yogurt or kefir, products made from acidified milk contain important ingredients that are good for our bodies. Acidified milk products provide:
- High-quality protein
- Calcium
- Potassium
- Magnesium
- Iodine
- Various vitamins
This ensures healthy bones, as well as the functioning of muscles, nerves and thyroid gland.
The positive effect of lactic acid bacteria.
Special bacteria also contribute to our well-being: Lactic acid bacteria are among the bioactives that strengthen our defenses. Studies have been able to show that added probiotic bacteria, which reach the intestine alive and ensure a healthy flora there, have an even more intensive and targeted effect. Natural yogurts without added sugar, thickeners or fruit preparations are also of particularly high quality. Unlike fruit yogurts, they are not usually heat-treated (pasteurized).As a result, they still contain living lactic acid bacteria that can develop their positive effect. By the way: Since the lactose in sour milk products is largely converted into lactic acid by the lactic acid bacteria, they are also usually well tolerated by people with lactose intolerance (lactose intolerance) – at least in smaller quantities.
