The primary objective of this study was to determine how yogurt ingredients affect aroma release in the mouth during eating. A model strawberry flavor consisting of ethyl butanoate, ethyl 3-methylbutanoate, (Z)-hex-3-enol, 2-methylbutanoic acid, 5-hexylhydro-2(3H)-furanone, and 3-methyl-3-phenylglycidic acid ethyl ester was added to unflavored, unsweetened yogurt that had different added sweeteners and hydrocolloids. In all, 12 yogurt formulations were examined to determine the effects of gelatin, modified food starch, pectin, sucrose, high-fructose corn syrup, and aspartame on aroma release. Aroma release was monitored by breath-by-breath analysis (proton-transfer reaction−mass spectrometry) during eating of the test yogurts. Results showed aroma release of the ethyl butanoate, (Z)-hex-3-enol, and ethyl 3-methylbutanoate to be suppressed by sweeteners, with 55 DE high-fructose corn syrup having the greatest effect. Addition of thickening agents had no significant effect on the aroma release profiles of the compounds under study. Keywords: Proton-transfer reaction−mass spectrometry; yogurt; high-fructose corn syrup; aroma release; flavor release; breath-by-breath