~ August 2013 No.250 ~
Yogurt has a long history, especially in Eastern Europe. It is generally believed that this fermented milk product became popular after Issac Caruso, who was born in what to-day is part of Greece, started industrial production of yogurt in Spain in 1919 under the name Danone. Danone has since become a multi-national food producer, now centred in France. Yogurt is the most popular probiotic food worldwide.
The production of yogurt requires the action of two bacteria - Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus on milk. The action of the bacteria, lowers the pH of the milk, which in turn thickens it, and results in the sour taste characteristic of natural yogurt. Yogurt is produced and consumed around the world; many different yogurts are now available. Yogurts with different levels of fat, or no fat, yogurts with a variety of flavours using natural or artificial flavourings, yogurts with other bacteria added, and yogurts with added jams or fruit pieces can now be found.
Food guide recommendations in most countries encourage the consumption of dairy products as a way of ensuring adequate calcium intakes. Yogurt is, therefore, often recommended as one possible dairy food for young and old alike. For example, Canada's Food Guide states a healthy diet should include two to four daily servings of dairy products: 175 g of yogurt is considered as one serving.
The appearance of “Greek style” yogurt may at first glance appear to be just an advertising ploy. But the method used to produce Greek style yogurt is different, and it does produce a yogurt that has an especially rich and creamy texture. The key is starting with more milk, and adding a straining step using cheesecloth. The unique texture is due to the formation of a tighter, more cross-linked denser protein gel network. The process also reduces the lactose content, making the final product even more acceptable to those with lactose intolerance. Greek yogurt also has a higher protein content than yogurts produced by other processes.