|MadSci Network: Microbiology|
Probably not. In order to make yogurt one needs milk and two different bacteria. Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus. Both of these organisms are present in yogurt you purchase at the local market but most likely not at optimum concentrations or proportions. It is possible that raw milk or even pasteurized milk may contain some lactic acid bacteria but raw milk may also contain dangerous bacteria and pasteurized milk most likely contains spoilage bacteria. If you want to make your own yogurt your best bet is to heat your milk and add a starter. If you do not have a starter try adding some yogurt to the milk.
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