How is unsweetened plant-based yogurt possible?
Actually, the yogurt cultures, usually some strain of the group N Streptococcus and Leuconostoc species, mesophilic cultures, converts the lactose into lactic acid, which gives the diary product it's tart taste.
Furthermore, bacterial enzymes transform the milk carbohydrates into oligosaccharides, some of which have prebiotic properties.
Different LAB (Lactic Acid Bacteria) produce different fermentation products, although they have in common that they are alive in the product and can interact with microbiota during intestinal transit and the cells of the intestinal wall.
Fermentation of soy milk with lactic acid bacteria offers a means of
preserving soy milk and the possibility of modifying the characteristic
flavor and texture to make it more acceptable to Western taste.
It is possible to make soy milk yogurt-like products with acceptable texture
and clean acid flavor. The choice of fermenting organisms is limited to
those that can ferment the sugars typical of soy milk. i.e. stachyose.
raffinose or sucrose. unless sugars fermented by the desired cultures
are added to the soy milk.
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