Influence of mastication and saliva on aroma release in a model mouth system

The influence of mastication, saliva composition and saliva volume on aroma release from rehydrated diced bell peppers and French beans was studied in a model mouth system. Released volatile compounds were analysed by gas chr omatography combined with sniffing port and flame ionisation detection. Com pounds were identified by gas chromatography/mass spectrometry, resulting i n more than 40 compounds to be identified in each vegetable. Mastication in creased release from bell peppers significantly and increased the number of volatile compounds with detectable odours in sniffing port analysis from s ix to 10 compounds. Addition of artificial or human saliva resulted in the same aroma profile for bell peppers. The amylase activity of artificial sal iva consisting of human or porcine alpha-amylase was in the same range as a mylase activity in human saliva at 37 degrees C. Bacterial alpha-amylase ha d lower activity. Human and porcine alpha-amylase in artificial saliva adde d to rehydrated French beans did not differ significantly in starch breakdo wn and affected aroma release similarly. Increase in saliva volume decrease d release of aroma compounds from rc:hydrated French brans significantly. T he artificial saliva with porcine or human alpha-amylase sufficiently simul ated human saliva with regard to aroma release. The three parameters mastic ation, saliva composition and saliva volume were shown to be important fact ors in aroma release from rehydrated vegetables. (C) 2000 Elsevier Science Ltd. All rights reserved.