Yogurt, buttermilk, kefir, sour cream - sour milk products are part of many people's daily diet. And rightly so: buttermilk and Co. not only taste really good, but are also still healthy. It is not only the protein and the vitamins that contribute to this, but also the lactic acid bacteria, which 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 diversity? Most sour milk products are initially produced in a similar process mainly from cow's milk, but also from goat, sheep or soy milk.
In order to obtain yoghurt, certain lactic acid bacteria are added to the milk, which utilize part of the milk. The milk sugar (lactose) present in the milk is converted into lactic acid. In this process, the milk curdles, which gives the yoghurt its fresh, sour taste and also makes it so wholesome.
By the way: The word "yoghurt" comes from the Turkish "yoghurmak" which means "thickening".
Right and left turning lactic acid
The lactic acid is usually present as a mixture of two forms, designated as right- or left-handed. Right-handed L (+) - lactic acid also occurs in human metabolism and is therefore easily digestible. It helps to gain energy in metabolism and protects the intestinal mucosa.
On the other hand, levorotatory D (-) lactic acid is degraded more slowly - and is therefore not recommended for infants under twelve months and people with intestinal diseases. On products containing only the more digestible dextrorotatory form, this is stated on the package.
How do you make buttermilk, kefir & Co.?
In addition to yoghurt, 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 procedure is used as for yoghurt, but on the basis of cream. Depending on the fat content of the product should be removed from the cream different amounts of water. So sour cream comes to at least 10, sour cream to at least 20 and creme fraiche to at least 30 percent fat.
- Buttermilk, like kefir, is different in its production from other acidic dairy products. Buttermilk is actually a waste product left over from sour cream butter. It contains similar nutrients as milk, but is significantly lower in fat.
- For the preparation of kefir, so-called kefir rolls - a mixture of yeasts and bacteria - are added to the milk. In addition to lactic acid, they also form small amounts of alcohol and carbon dioxide. That's why Kefir bubbles up a little. The product is easy to digest, contains many B vitamins and has a positive effect on intestinal activity. Because of these properties, kefir is also referred to as the "drink of centenarians".
- Whey is a liquid that separates in making quark and cheese. Sweet whey is produced by thickening the milk with rennet (a calf stomach enzyme), especially in cheese production, and sour whey in the coagulation processes caused by lactic acid bacteria (especially in quark preparation). Whey is very low in fat and low in calories and contains high-quality protein, especially B vitamins and minerals such as potassium and calcium.
Ingredients of sour milk products
Whether buttermilk, yogurt or kefir: Products made from leavened milk contain important ingredients that are good for our body. Sour milk products provide:
- high quality protein
- different vitamins
This ensures healthy bones as well as the functioning of muscles, nerves and thyroid.
The positive effect of lactic acid bacteria
The special bacteria contribute to our well-being: Lactic acid bacteria are among the bioactive substances that strengthen our defenses. Studies have shown that added probiotic bacteria that reach the intestine alive and provide a healthy flora there, even more intense and targeted.
In addition, natural yoghurts without added sugar, thickening agents or fruit preparations are of particularly high quality. They are usually not heat treated (pasteurized) unlike fruit yoghurts. As a result, they still contain living lactic acid bacteria, which can develop their positive effects.
Incidentally, lactose is largely converted into lactic acid by the lactic acid bacteria in sour milk products, and these are usually well tolerated by people with lactose intolerance (lactose intolerance), at least in smaller quantities.