Saliva has a buffer capacity which neutralizes acids in the mouth. This capacity is based on several systems such as the phosphate system and the carbonic acid/bicarbonate system. In Ericsson's method saliva was collected and stimulated for 5 minutes. 1.0 ml of the saliva is transferred to 3.0 ml HCl, For preventing the foaming, one drop of 2-octanol is added and mixed for 20 minutes to remove CO2. Finally pH in the saliva is evaluated electrometrically.