Yoghurt
From Wikipedia, the free encyclopedia
Yoghurt or yogurt, less commonly yoghourt or yogourt (see spelling below), is a dairy product produced by bacterial fermentation of milk. Fermentation of the milk sugar (lactose) produces lactic acid, which acts on milk protein to give yoghurt its texture and its characteristic tang. Soy yogurt, a dairy yoghurt alternative, is made from soy milk.
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[edit] History
Yoghurt, full fat Nutritional value per 100 g (3.5 oz) |
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Energy 60 kcal 260 kJ | |||||||||||||
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(*) Lactose content diminishes during storage. Percentages are relative to US recommendations for adults. Source: USDA Nutrient database |
There is evidence of cultured milk products being produced as food for at least 4,500 years. The earliest yoghurts were probably spontaneously fermented by wild bacteria living on the goat skin bags carried by the Bulgars (or Hunno-Bulgars), a nomadic people who began migrating into Europe in the second century AD and eventually settled in the Balkans at the end of the seventh century. Today, many different countries claim yoghurt as their own,[citation needed] yet there is no clear evidence as to where it was first discovered.
The use of yoghurt by mediaeval Turks is recorded in the books Diwan Lughat al-Turk by Mahmud Kashgari and Kutadgu Bilig by Yusuf Has Hajib written in the eleventh century. In both texts the word "yoghurt" is mentioned in different sections and its use by nomadic Turks is described. The first account of a European encounter with yoghurt 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 yoghurt.
Until the 1900s, yoghurt was a staple in diets of the South Asian, Central Asian, Western Asian, South Eastern European and Central European regions. The Russian biologist Ilya Ilyich Mechnikov had an unproven hypothesis that regular consumption of yoghurt was responsible for the unusually long lifespans of Bulgarian peasants. Believing Lactobacillus to be essential for good health, Mechnikov worked to popularise yoghurt as a foodstuff throughout Europe. It fell to a Sephardic Jewish entrepreneur named Isaac Carasso to industrialise the production of yoghurt. In 1919, Carasso, who was from Salonika, started a small yoghurt business in Barcelona and named the business Danone ("little Daniel") after his son. Carasso emigrated to the United States during World War II and set up a business in New York City under an Americanised version of the name: Dannon. Yoghurt with added fruit jam was invented to protect yoghurt from decay. It was patented in 1933 by the Radlická Mlékárna dairy in Prague, and introduced to the United States in 1947, by Dannon.
Yogurt's popularity in the United States was enhanced in the 1950's and 60's when it was presented as a health food.
[edit] Culture
Yoghurt is made by introducing specific bacteria strains into milk, which is subsequently fermented under controlled temperatures and environmental conditions (inside a bioreactor), especially in industrial production. The bacteria ingest natural milk sugars and release lactic acid as a waste product. The increased acidity causes milk proteins to tangle into a solid mass (curd) in a process called denaturation. The increased acidity (pH=4–5) also prevents the proliferation of potentially pathogenic bacteria. In the U.S., to be named yoghurt, the product must contain the bacteria strains Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. Often these two are co-cultured with other lactic acid bacteria for taste or health effects (See probiotics). These include L. acidophilus, L. casei and Bifidobacterium species. In most countries, a product may be called yoghurt only if live bacteria are present in the final product. In the U.S., non-pasteurised yoghurt can be marketed as "live" or containing "live active culture". A small amount of live yoghurt can be used to inoculate a new batch of yoghurt, as the bacteria reproduce and multiply during fermentation. Pasteurised products, which have no living bacteria, are called fermented milk (drink).
[edit] Benefits
Yoghurt has nutritional benefits beyond those of milk: people who are moderately lactose-intolerant can enjoy yoghurt without ill effects, because the lactose in the milk precursor is converted to lactic acid by the bacterial culture. The reduction of lactose bypasses the affected individuals' need to process the milk sugar themselves.[1]
Yoghurt also has medical uses, in particular for a variety of gastrointestinal conditions,[2] and in preventing antibiotic-associated diarrhea.[3] One study suggests that eating yoghurt containing L. acidophilus helps prevent vulvovaginal candidiasis, though the evidence is not conclusive.[4]
[edit] Presentation
To offset its natural sourness, yoghurt can be sold sweetened, flavored, or in containers with fruit or fruit jam on the bottom.[5] If the fruit has been stirred into the yoghurt before purchase, it is commonly referred to as Swiss-style.[6] Most yoghurts in the United States have added pectin or gelatin. Some specialty yoghurts have a layer of fermented fat at the top[citation needed]. Fruit jam is used instead of raw fruit pieces in fruit yoghurts to allow storage for weeks.[citation needed] "Strained" yoghurt is the concentrated residue (described as a sort of "yoghurt cheese") produced by filtering plain yoghurt that is without flavorings, gelatin, pectin, or other additives through a paper or cloth filter, and allowing water and whey to drain away.
[edit] Varieties
- Strained yoghurts, which include Greek Yoghurt (yiaourti), Dahi and Bulgarian Yoghurt are types of yoghurt which are strained through a cloth or paper filter, traditionally made of muslin, to remove the whey, giving a much thicker consistency, and a distinctive, slightly tangy taste. Some types are boiled in open vats first, so that the liquid content is reduced. The popular East Indian dessert, Mishti Dahi, is a variation of traditional Dahi, offers a thicker, more custard-like consistency, and is usually sweeter than western yoghurts.
- Dadiah, or Dadih, is a traditional West Sumatran yoghurt made from water buffalo milk. It is fermented in bamboo tubes.
- Labneh yoghurt of Lebanon is a thickened yoghurt used for sandwiches. Olive oil, cucumber slices, olives, and various green herbs may be added. It can be thickened further and rolled into balls, preserved in olive oil, and fermented for a few more weeks. It is sometimes used with onions, meat, and nuts as a stuffing for a variety of Lebanese pies or Kebbeh ( كبة ) balls.
- Tarator/cacık is a popular cold soup made from yoghurt, popular during summertime in Bulgaria, Macedonia, and Turkey. It is made with Ayran, cucumbers, dill, salt, olive oil, and optionally garlic and ground walnuts in Bulgaria, and generally without walnuts in Turkey.
- Rahmjoghurt, a creamy yoghurt with much higher milkfat content (10%) than most yoghurts offered in English-speaking countries (Rahm is German for cream), is available in Germany and other countries.
- Caspian Sea Yoghurt is believed to have been introduced into Japan in 1986 by researchers returning from a trip to the Caucasus region in Georgia[7]. This variety, called Matsoni, is started with Lactococcus lactis subsp. cremoris and Acetobacter orientalis species and has a unique, viscous, honey-like texture.[8] It is milder in taste than other varieties of yoghurts. Ideally, Caspian Sea yoghurt is made at home because it requires neither special equipment nor unobtainable culture. It can be made at room temperature (20–30°C) in 10 to 15 hours.[9] In Japan, freeze-dried starter cultures are sold in department stores and online, although many people obtain starter cultures from friends.[citation needed]
- Jameed is yoghurt which is salted and dried to preserve it. It is popular in Jordan.
[edit] Drinks
- Ayran is a yoghurt-based, salty drink popular in Turkey, Azerbaijan, Iran, Bulgaria, Macedonia, Kazakhstan and Kyrgyzstan. It is made by mixing yoghurt with water and adding salt. The same drink is known as "Tan" in Armenia, "Laban Ayran" in Syria and Lebanon, "Shenina" in Jordan, "Moru" in South India, and "Laban Arbil" in Iraq. A similar drink, doogh, is popular in the Middle East between Lebanon and Afghanistan; it differs from ayran by the addition of herbs, usually mint, and is carbonated, usually with seltzer water.
- Lassi is a yoghurt-based beverage originally from the Indian subcontinent that is usually slightly salty or sweet. Lassi is a staple of Punjab, in some parts of the subcontinent, the sweet version may be commercially flavored with rosewater, mango or other fruit juice to create a totally different drink. Salty lassi is usually flavored with ground, roasted cumin and red chillies, this salty variation may also use buttermilk, and is interchangeably called Mattha (North India), Tak(Maharashtra), or Chaas (Gujarat).
- Kefir is a fermented milk drink originating in the Caucasus. A related Central Asian Turco-Mongolian drink made from mare's milk is called kumis, or airag in Mongolia. Some American dairies have offered a drink called "kefir" for many years with fruit flavours but without carbonation or alcohol.
- Sweetened Yoghurt Drinks are the usual form in the US and UK containing fruit and added sweeteners. These are typical called "drinking / drinkable yoghurt". Also available are "yoghurt smoothies" which contain a higher proportion of fruit and are more like Smoothies.
[edit] Homemade
Yoghurt is customarily made in domestic environments in regions where yoghurt has an important place in traditional cuisine. It can be made by scalding milk, cooling it to just above body temperature, and then adding a small amount of previously made yoghurt (for example, store-bought, plain, live-culture yoghurt). The mixture is kept at the warm temperature for several hours, during which fermentation (proliferation of the bacteria that were in the previously made yogurt) causes it to become yoghurt.[10] Special yoghurt-making machines assist in small-batch yoghurt-making.[11] In 2005, Mireille Guiliano released her best selling book, French Women Don’t Get Fat, in which she touts yogurt as her secret weight loss weapon. In her book, she campaigned for Americans to discover the benefits and pleasures of homemade plain, non-fat yogurt, as opposed to the sugar and corn syrup-laden ‘impostors’ found in most U.S. supermarkets.
[edit] Etymology and spelling
The word is derived from Turkish yoğurt,[12] and is related to yoğurmak 'to knead' and yoğun 'dense' or 'thick'.[13]. The letter ğ was traditionally rendered as "gh" in transliterations of Turkish, which used to be written in a variant of the Arabic alphabet until the introduction of the Latin alphabet in 1928. In older Turkish the letter denoted a voiced velar fricative /ɣ/, but this sound is elided between back vowels in modern Turkish, in which the word is pronounced [joˈuɾt]. Some eastern dialects retain the consonant in this position, and Turks in the Balkans pronounce the word with a hard /g/.
In English, there are several variations of the spelling of the word. In the United States, yogurt is the usual spelling and yoghurt a minor variant. In the United Kingdom, yoghurt and yogurt are both current, yoghurt being more common, and yoghourt is an uncommon alternative.[14] Canada uses mostly yogurt and yogourt, the latter being particularly common in bilingual packaging, as it is also the spelling in Canadian French; in Australia and New Zealand yoghurt prevails.[15][16]
Whatever the spelling, the word is pronounced with either a short "o" or a long "o" in the UK and New Zealand, and with a long "o" in North America, Ireland and Australia (UK IPA: /ˈjɒgət/ or /'jəʊgət/; North America /'joʊgɚt/; Australia /'jəʉgət/).
- Further information: American and British English spelling differences
[edit] References
- ^ Yogurt--an autodigesting source of lactose. J.C. Kolars et al., New England Journal of Medicine, 310:1-3 (1984)
- ^ O. Adolfsson et al., "Yogurt and gut function", American Journal of Clinical Nutrition 80:2:245-256 (2004) [1]
- ^ Ripudaman S. Beniwal, et al., "A Randomized Trial of Yogurt for Prevention of Antibiotic-Associated Diarrhea", Digestive Diseases and Sciences 48:10:2077-2082 (October, 2003) doi:10.1023/A:1026155328638
- ^ Erika N. Ringdahl, "Treatment of Recurrent Vulvovaginal Candidiasis", American Family Physician 61:11 (June 1, 2000)
- ^ http://www.askdrsears.com/faq/fn12.asp
- ^ http://web.foodnetwork.com/food/web/encyclopedia/termdetail/0,7770,1184,00.html
- ^ The Japan Times Bacteria spreads across nation to create slimy, healthy treat, By TAKUYA KARUBE Kyodo News
- ^ Health and Nutrition News
- ^ Japan's #1 English Magazine, Health and Beauty, Yogurt Yo
- ^ http://www.uga.edu/nchfp/publications/nchfp/factsheets/yogurt.html
- ^ http://homecooking.about.com/library/weekly/aa031102b.htm Home-made yoghurt, machines]
- ^ Merriam-Webster Online - Yogurt entry
- ^ Ahmet Toprak's article
- ^ Peters, Pam (2004). The Cambridge Guide to English Usage. Cambridge: Cambridge University Press, pp. 587-588.
- ^ "yoghurt n." The Australian Oxford Dictionary, 2nd edition. Ed. Bruce Moore. Oxford University Press, 2004. Oxford Reference Online. Accessed on 2007-05-24.
- ^ "yoghurt n." The New Zealand Oxford Dictionary. Tony Deverson. Oxford University Press 2004. Oxford Reference Online. Accessed on 2007-05-24.
[edit] See also
[edit] External links
- US National Center for Home Food Preservation: Fermenting Yogurt at Home
- Yogurt Forever: The Yogurt EncyclopediaPDF (259 KiB)
- DHA, EPA & Probitotic Yogurt FAQ
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