Salivary protein profiles and sensitivity to the bitter taste of caffeine

Chem Senses. 2012 Jan;37(1):87-95. doi: 10.1093/chemse/bjr070. Epub 2011 Aug 25.


The interindividual variation in the sensitivity to bitterness is attributed in part to genetic polymorphism at the taste receptor level, but other factors, such as saliva composition, might be involved. In order to investigate this, 2 groups of subjects (hyposensitive, hypersensitive) were selected from 29 healthy male volunteers based on their detection thresholds for caffeine, and their salivary proteome composition was compared. Abundance of 26 of the 255 spots detected on saliva electrophoretic patterns was significantly different between hypo- and hypersensitive subjects. Saliva of hypersensitive subjects contained higher levels of amylase fragments, immunoglobulins, and serum albumin and/or serum albumin fragments. It also contained lower levels of cystatin SN, an inhibitor of protease. The results suggest that proteolysis occurring within the oral cavity is an important perireceptor factor associated to the sensitivity to the bitter taste of caffeine.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Caffeine / pharmacology*
  • Humans
  • Male
  • Middle Aged
  • Saliva / chemistry*
  • Salivary Proteins and Peptides / analysis*
  • Salivary Proteins and Peptides / metabolism*
  • Taste / drug effects*
  • Taste / physiology*
  • Taste Threshold / drug effects
  • Taste Threshold / physiology


  • Salivary Proteins and Peptides
  • Caffeine