With precision fermentation, bioengineering techniques are used to program microorganisms by giving them a specific genetic code to produce a compound of interest when fermented under precise conditions. The genetic code is the exact copy of the DNA sequence found in a digitized database on animal or plant DNA sequence; however, it requires no animal or plant involvement. The result is a molecularly identical ingredient produced by microorganisms.
Source: The future is now for precision fermentation | Food Business News