Yoghurt

Yogurt, yoghurt, or yoghourt (/ˈjoʊɡərt/ or /ˈjɒɡət/; from Turkish: yoğurt; other spellings listed below) is a fermented milk productproduced by bacterial fermentation of milk. The bacteria used to make yogurt are known as "yogurt cultures". Fermentation of lactoseby these bacteria produces lactic acid, which acts on milk protein to give yogurt its texture and its characteristic tang.^[1]

Worldwide, cow's milk, the protein of which is mainly casein, is most commonly used to make yogurt. Milk from water buffalo, goats,ewes, mares, camels, and yaks however, is also used to produce yogurt in various parts of the world.

Dairy yogurt is produced using a culture of Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus bacteria. In addition, other lactobacilli and bifidobacteria are also sometimes added during or after culturing yogurt. Some countries require yogurt to contain a certain amount of colony-forming units of microorganisms.^[2]

In Western culture, the milk is first heated to about 80 °C (176 °F) to kill any undesirable bacteria^{[citation needed]} and to denature the milk proteins so that they set together rather than form curds. In some places, such as parts of India & Bangladesh curds are a desired component and milk is not pasteurized but boiled. The milk is then cooled to about 45 °C (112 °F).^{[citation needed]} The bacterial culture is added, and the temperature of 45 °C is maintained for 4 to 7 hours to allow fermentation.

History

By most accounts yogurt was created by Central Asian people in the Neolithic.^[14] Analysis of the L.

delbrueckii subsp. bulgaricus genome indicates that the bacterium may have originated on the surface of a plant.^[15] Milk may have become spontaneously and unintentionally infected through contact with plants, or bacteria may have been transferred via the udder of domestic milk-producing animals.^[16]

In ancient Indian records, the combination of yogurt and honey is called "the food of the gods".^[17] Persian traditions hold that "Abraham owed his fecundity and longevity to the regular ingestion of yogurt".^[18]

The oldest writings mentioning yogurt are attributed to Pliny the Elder, who remarked that certain "barbarous nations" knew how "to thicken the milk into a substance with an agreeable acidity".^[19] The use of yogurt by medieval Turks is recorded in the books Diwan Lughat al-Turk by Mahmud Kashgari and Kutadgu Bilig by Yusuf Has Hajib written in the 11th century.^[20][21] Both texts mention the word "yogurt" in different sections and describe its use by nomadic Turks.^[20][21] The earliest yogurts were probably spontaneouslyfermented by wild bacteria in goat skin bags.^[22]

Some accounts suggest that Indian emperor Akbar's cooks would use mustard seeds and cinnamon in yogurt to add flavor to it.^[23] Another early account of a European encounter with yogurt occurs in French clinical history: Francis I suffered from a severe diarrhea which no French doctor could cure. His ally Suleiman the Magnificent sent a doctor, who allegedly cured the patient with yogurt.^[23][24] Being grateful, the French king spread around the information about the food which had cured him.

Until the 1900s, yogurt was a staple in diets of people in the Russian Empire (and especially Central Asia and the Caucasus), Western Asia, South Eastern Europe/Balkans, Central Europe, and India. Stamen Grigorov (1878–1945), a Bulgarian student of medicine in Geneva, first examined the microflora of the Bulgarian yogurt. In 1905, he described it as consisting of a spherical and a rod-like lactic acid bacteria. In 1907, the rod-like bacterium was called Bacillus bulgaricus (now Lactobacillus delbrueckii subsp. bulgaricus). TheRussian Nobel laureate and biologist Ilya Ilyich Mechnikov (also seen as Élie Metchnikoff), from the Institut Pasteur in Paris, was influenced by Grigorov's work and hypothesized that regular consumption of yogurt was responsible for the unusually long lifespans of Bulgarian peasants. Believing Lactobacillus to be essential for good health, Mechnikov worked to popularize yogurt as a foodstuff throughout Europe.

Isaac Carasso industrialized the production of yogurt. In 1919, Carasso, who was from Ottoman Salonika, started a small yogurt business in Barcelona, Spain, and named the business Danone ("little Daniel") after his son. The brand later expanded to the United States under an Americanized version of the name: Dannon.

Yogurt with added fruit jam was patented in 1933 by the Radlická Mlékárna dairy in Prague.^[25]

Yogurt was introduced to the United States in the first decade of the twentieth century, influenced by Élie Metchnikoff's The Prolongation of Life; Optimistic Studies (1908); it was available in tablet form for those with digestive intolerance and for home culturing.^[26] It was popularized by John Harvey Kellogg at the Battle Creek Sanitarium, where it was used both orally and in enemas,^[27] and later by Armenian immigrants Sarkis and Rose Colombosian, who started "Colombo and Sons Creamery" in Andover, Massachusetts in 1929.^[28][29] Colombo Yogurt was originally delivered around New England in a horse-drawn wagon inscribed with the Armenian word "madzoon" which was later changed to "yogurt", the Turkish name of the product, as Turkish was the lingua franca between immigrants of the various Near Eastern ethnicities who were the main consumers at that time. Yogurt's popularity in the United States was enhanced in the 1950s and 1960s, when it was presented as a health food. By the late 20th century, yogurt had become a common American food item and Colombo Yogurt was sold in 1993 to General Mills, which discontinued the brand in 2010.^[30]

There is an ongoing effort by Byron-Bergen Elementary School to make Yogurt the official snack food of New York State. ^[31] [32]

Nutritional value and health benefits

Unstirred Turkish Süzme Yoğurt(strained yogurt), with a 10% fat content

Yogurt is nutritionally rich in protein, calcium, riboflavin, vitamin B6 and vitamin B12.^[33] It has nutritional benefits beyond those of milk.Lactose-intolerant individuals can sometimes tolerate yogurt better than other dairy products, because the lactose in the milk is converted toglucose and galactose, and partially fermented to lactic acid, by the bacterial culture.^[34]

Yogurt containing live cultures has been found effective at preventing antibiotic-associated diarrhea.^[35] Yogurt contains varying amounts offat. There is non-fat (0% fat), low-fat (usually 2% fat) and plain or whole milk yogurt (4% fat).^[36] A study published in the International Journal of Obesity (11 January 2005) also found that the consumption of low-fat yogurt can promote weight loss, relative to a gelatin placebo.^[37]

Yogurt is a valuable health food for both infants and elderly persons. For children, it is a balanced source of protein, fats, carbohydrates, and minerals. For senior citizens, who frequently have more sensitive colons or who no longer produce much lactase, yogurt is also a valuable food. Elderly intestines showed declining levels of bifidus bacteria, which allow the growth of toxin-producing and, perhaps, cancer-causing bacteria. Yogurt may help prevent osteoporosis, reduce the risk of high blood pressure. Yogurt with active cultures helps the gut, may discourage vaginal infections, and may help one feel fuller.^[38]

The "yogurt defense" was made famous by the trial of Carol Downer, one of the developers of menstrual extraction. She was arrested at her self-help group and charged with practicing medicine without a license, as she inserted yogurt into the vagina of another woman to treat a yeast condition. Carol Downer was acquitted; the jury did not equate inserting yogurt with practicing medicine.^[39]