Fermentation of carbohydrates
Fermentation of carbohydrates during the formation of acid can be used to identify bacteria and here is a table of carbohydrates, which are often used for identification, and whether the current bacterium can ferment one or several of them.
Lactose + indicates that the bacterium ferments lactose under acid production.
Note that glucose(gas) - indicates that the bacterium does not ferment glucose under gas formation.
V (or v) means variable, i.e. that some strains of the bacterial species in question ferment carbohydrates, while other strains do not. W (or w) stands for weak, which means that it takes time before the pH change takes place or that the pH change is not so strong.