Yogurt, also written yogourt and yoghurt, is a dairy product that is most commonly made of cow’s milk, but can be made from the milk of a variety of animals. It is a good part of a balanced diet because it is rich in protein, calcium, vitamin B6 and B12. There are many different varieties of yogurt, but the sweetened and flavored varieties are the most popular in the Western World. If you have ever wondered how yogurt is made, keep reading to find out.
How is yogurt made?
The ingredients of yogurt consist of milk (usually cow’s milk), bacteria cultures (Streptococcus thermophilus and Lactobacillus bulgaricus). Some manufacturers also use the cultures of Lactobacillus acidophilus and bifidobacteria. When manufacturing sweet yogurt flavors (usually fruit jam) and sweeteners are also added.
The manufacture of yogurt beings by heating the milk within the range of 80-93 °C (176-200 °F). This kills any undesirable microorganisms and denatures the proteins in milk to form curds. The milk is then cooled to around 45 °C (113 °F) and the bacteria cultures are added. This temperature is maintained, or slightly lowered to 37° C (100° F), for about 4-7 hours for fermentation to take place. During this time the bacteria consume the natural sugar in the milk and excrete lactic acid, which further curdles the milk to create the more solid yogurt consistency. Flavors and sweeteners are also usually added at this time. The longer this mixture is left the more tart the yogurt will be because the bacteria will produce more lactic acid. To stop the fermentation process the yogurt is placed in refrigeration where it can be stored for a limited period of time.
Did you know?
The bacteria cultures used in yogurt are not harmful bacteria. In fact, some of the bacteria used in yogurt have been shown to have health benefits.