A century ago, few Americans had ever heard of yogurt. Although people have been eating the tangy treat for more than 4,000 years, it did not become popular in the United States until the 1960s.
Now, yogurt consumption in the U.S. is rapidly rising.
Per capita yogurt consumption in the U.S. in 2010 was 11.5 pounds, about 6 times less than in Europe. Some industry experts expect U.S. yogurt consumption to double by 2015.
Production of yogurt was developed to preserve milk in warm climates. Its high acid content prevents the growth of pathogenic and spoilage bacteria. Roman philosopher Gaius Secundus mentioned the consumption of yogurt in the first century AD. A journal from the 1100s describes yogurt.
Nutritionists have associated health benefits with eating yogurt. Physicians prescribed a daily regimen of yogurt to successfully treat 15th century king Francis I of France, who had an intestinal disorder.
Yogurt is made through the bacterial fermentation of whole milk containing a high concentration of solids – protein and fat. Lactobacillus bulgaricus and Streptococcus thermophilus are the bacteria species that are most commonly used to produce yogurt. However, some yogurt companies include other species of bacteria in their starter cultures.
Middle Eastern nomads coined the word “yogurt” from the Turkish word for “thicken.” The semi-solid fraction of yogurt consists of denatured protein and fat. The denatured protein causes the milk to thicken. The bacteria ferment the milk sugar lactose into lactic acid. Lactic acid imparts a sour – or tangy – flavor.
The pH of yogurt is about 4.0 to 4.5 – mildly acidic. The tan-colored liquid that forms at the top of a container of yogurt upon standing is whey. Whey forms after protein curdles. It contains soluble milk protein, unfermented lactose, minerals, and vitamins.
Yogurt is a nutrient-rich food. One cup – 8 ounces – of plain low-fat yogurt typically contains 150 calories of energy and 13 grams of protein. The protein content is 23 percent of the recommended daily protein intake for adults. One cup of low-fat yogurt contains 3 g of fat, most of which is saturated fat. The mineral content of one cup of yogurt is high in calcium, phosphorus, magnesium, potassium, zinc, copper, and selenium. Also, low-fat yogurt is rich in riboflavin, pantothenic acid, and vitamin B12.
Many Americans dislike the sour taste of plain yogurt, so processors add strawberries, blueberries, raspberries, or other fruits to the plain yogurt. In 1947, commercial yogurt producer Dannon introduced fruit on the bottom of the container to the U.S. market.
According to a recent article in the Huffington Post, yogurt sales in the U.S. have increased an average 113 percent every year since 2001. The article also pointed out that yogurt is most popular among Americans 18 to 34 years old.
Greek yogurt is experiencing rapidly growing popularity in the U.S., and now accounts for about a third of total sales. Total U.S. yogurt sales were $4.03 billion in 2011. According to the Huffington Post, Greek yogurt sales soared 2,500 percent between 2006 and 2011.
One major difference between regular and Greek yogurt is that processors strain Greek yogurt through cheesecloth or muslin to remove the liquid whey. This concentrates the nutrients in the yogurt. One 8-ounce cup of Greek yogurt contains 20 to 30 grams of protein and 18 to 20 grams of fat. Greek yogurt contains less calcium than regular low-fat yogurt. This is because the straining process removes some of the calcium from the yogurt. In addition, Greek yogurt is generally more expensive than regular yogurt.
Dom Castaldo, Ph.D., is a nutritionist and a microbiology instructor at Sauk Valley Community College in Dixon. He welcomes comments via email at HYPERLINK “mailto:firstname.lastname@example.org” email@example.com.