Question: Is it possible to make authentic yogurt from plant sources?
About the article "Yogurt", section "Non-dairy yogurt substitutes".

Candidate passages:
Various manufacturers have endeavoured to produce plant-based substitutes for yogurt, using soy milk, nut milks such as almond milk, and coconut milk, for consumers who are unable to tolerate dairy products in any form.
Although "Lactobacillus" strains exist that can produce lactic acid from plant-derived feed stock ("e.g."
sauerkraut), since plants do not produce lactose, it is not possible to produce genuine yogurt from plant sources with the same bacteria cultures used to convert milk into yogurt.
The origins of yogurt are unknown.
Analysis of the "L. delbrueckii" subsp.
"bulgaricus" genome indicates that the bacterium may have originated on the surface of a plant.
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.
In ancient Indian records, the combination of yogurt and honey is called "the food of the gods".
Persian traditions hold that "Abraham owed his fecundity and longevity to the regular ingestion of yogurt".
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".
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.
Both texts mention the word "yogurt" in different sections and describe its use by nomadic Turks.
The earliest yogurts were probably spontaneously fermented by wild bacteria in goat skin bags.
Some accounts suggest that Indian emperor Akbar's cooks would use mustard seeds and cinnamon in yogurt to add flavor.
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.
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").
The Russian 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.
Yogurt was first 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.
It was popularized by John Harvey Kellogg at the Battle Creek Sanitarium, where it was used both orally and in enemas, and later by Armenian immigrants Sarkis and Rose Colombosian, who started "Colombo and Sons Creamery" in Andover, Massachusetts in 1929.
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.
There is an ongoing effort by Byron-Bergen Elementary School to make Yogurt the official snack food of New York State. 
It would be difficult to prove unequivocally the origin of Bulgarian yogurt, but the fact is that Bulgaria has a strong tradition of making yogurt.
Traditionally Bulgarians have consumed a notable quantity of yogurt per head and is noted historically for the production of high quality yogurt, including using a unique variety of micro-organism called "Lactobacillus bulgaricus" in the manufacturing process.
It has even been claimed that yogurt originates from Bulgaria.
Though this cannot be substantiated, Bulgaria has been part of a region that has cultivated and consumed yogurt from as far back as 3000 BC.
Some historians view the Balkans as the “homeland” of yogurt. 
Brown Cow is an American brand of yogurt produced in Antioch, California.
The company offers a range of "cream top" yogurt—when the milk used to make yogurt has not been homogenized, a layer of cream rises to the top, forming a rich yogurt cream with a taste and texture like sour cream.
Brown Cow yogurt claims to contain all-natural ingredients, with no artificial ingredients or preservatives, and uses only milk from cows who were not treated with artificial growth hormones. 
Jameed (Arabic: جميد, literally "hardened") is an Arab food consisting of hard dry laban made from ewe or goat's milk.
Milk is kept in a fine woven cheesecloth to make a thick yogurt.
Salt is added daily to thicken the yogurt even more and the outside of the yogurt-filled cheesecloth is rinsed with water to allow any remaining whey to seep through.
After a few days of salting the yogurt, it becomes very dense and it can be removed from the cheesecloth and shaped into round balls.
It is then set to dry for a few days.
If it is dried in the sun it becomes yellow; if it is dried in the shade it remains white.
It is important that the jameed is dry to the core because any dampness can spoil the preservation process.
It is also often referred to as "rock cheese".