Deborah D. Roberts and Terry E. Acree*
Simulation of Retronasal Aroma Using a Modified Headspace Technique: Investigating the Effects of Saliva, Temperature, Shearing, and Oil on Flavor Release
J.Agric. Food Chem. Submitted:
A device which simulated retronasal aroma was constructed from a 1 Liter blender incorporating purge-and-trap, synthetic saliva addition, temperature regulation to 37 ¡C, and blending with a shear rate reported to occur during eating. Volatiles were collected on a silica trap, solvent desorbed, and quantitated by GC/FID or GC/MS. Temperature regulation and shearing were each found to increase volatility. The addition of synthetic saliva to a pH 2.6 model beverage increased the volatility of the bases, 2-acetylpyridine, methyl anthranilate, o-aminoacetophenone, and 2-methoxy-3-methylpyrazine relative to a model neutral compound, 1,8-cineole. A sensory test showed a perceptible flavor profile shift upon saliva addition. The volatility of eight flavor compounds was investigated in a soybean oil versus water matrix. The volatility of a-pinene, ethyl-2-methylbutyrate, 1,8-cineole, 2-methoxy-3-methylpyrazine and methyl anthranilate decreased by factors of 8000, 130, 100, 7, and 3 upon oil addition; however butyric acid did not decrease and polar maltol (log P = 0.02) actually increased.