| Overall, this research aims to better understand aroma release, aroma perception and techniques used in these studies. A comparison of mass spectral techniques, atmospheric pressure chemical ionization-mass spectrometry (APCI-MS) and proton transfer reaction-mass spectrometry (PTR-MS), was performed. The linear regions and detection limits for both instruments using common aroma compounds, ethyl butyrate, ethyl isovalerate, and cis-3-hexenol, showed both instruments performed comparably. Both instruments are commonly used in retronasal aroma release studies and were used in other parts of this research.; Next, a study of aroma release from strawberry flavor yogurt examined how the composition of a semi-solid food influences retronasal aroma concentration during consumption. Using PTR-MS for breath analysis, the release of ethyl butyrate, ethyl isovalerate, and cis-3-hexenol was found to be suppressed by the addition of sweeteners, with 55 DE high fructose corn syrup having the greatest effect.; Simultaneous sensory and instrumental studies help to better understand the link between aroma release and perception. Breath analysis (instrumental method) and just noticeable difference sensory analysis were used to determine how much the retronasal concentration of ethyl butyrate must change in order for people to perceive a difference. For ethyl butyrate concentrations ranging from 0 to 4 ppm in 2% sucrose solutions, a 60% change in retronasal ethyl butyrate concentration was required for the sensory panel to perceive a difference in aroma intensity.; To understand real-time aroma release and perception in a complex food, PTR-MS breath analysis and time intensity (TI) analysis were used to study the influence of composition, texture and serving temperature on aroma release from Cheddar cheese. A variety of factors, including cheese hardness, composition and temperature, were used to conduct statistical analysis of the release and perception of anethole, terpinolene, and trans-2-hexenol acetate. It was found that the maximum concentration of aroma in the nosespace and the maximum perceived intensity were influenced by manufacture date. The time to maximum for both nosespace and sensory results was primarily affected by serving temperature. |
