Microorganisms have been used as tools for the production of products for millennia. Even in ancient times, the ability to produce vinegar by allowing water to percolate through wood shavings was known and widely practiced. Likewise, the transformation of a yeast suspension into beer or a suspension of crushed grapes into wine was common knowledge. The basis of these events may not have been known, but that did not impede the sale or trade of such products.

These economic uses of microorganisms are the earliest examples of biotechnology. As the knowledge of bacteria and yeast-chemical behaviors grew, other biotechnological uses for the microbes were found. A few examples include the use of the bacterium Lactobacillus acidophilus to produce yogurt, the exploitation of a number of different bacteria to produce a variety of cheeses, and the fermentation of cabbage...