where does yeast come from

Yeast is a single-celled microorganism that belongs to the fungus kingdom. It is naturally found all around us in the environment, commonly on tree sap, grape skins, fallen fruits, and other sugary, decaying plant material. Yeast plays a crucial role in breaking down and fermenting sugars in these natural settings. The yeast used in baking and brewing, especially Saccharomyces cerevisiae, was domesticated from wild yeast strains, which people have utilized for thousands of years in making bread, beer, and wine. This domestication likely involved a mixture of strains from different regions, including Europe and Asia, spread along ancient trade routes like the Silk Road. Yeast has a long history dating back to ancient Egypt and China, with archaeological evidence showing its use in fermentation processes millennia ago. Essentially, yeast originally comes from nature, particularly from sugary, decaying vegetation, and has been cultivated and selected by humans for practical uses over a long period.