Madeleine M. Rochelle tested equal odds ratio of binary mixtures about three key food odorants (KFOs) in potato chips to explore the mechanisms of organisms decoding odor mixtures published in 2017. The goal of this project is testing odorants interactions in tertiary mixtures. In other words, how the change of concentration of third odorants affects the perception of binary mixtures. The selection of three odor compounds are based on the Rochelle’s research, three key odorants in potato chips including methional (MAL) with baked potato nots, methanethiol (MOL) with rotten cabbage notes, and 2-ethyl-3,5-dimethylpyrazine (2E3,5DP) with toast notes. Sniff Olfactometry (SO) was used to measure threshold of each odorant, EOR of binary mixtures, and EOR of tertiary mixtures after 70ms stimulations for 4 subjects. However, three subjects were screened out , because they did not pass the pre-testing or recognition test. Even though the number of subjects is limited, the project set up an initial to proceed the experiment procedures, so that future research could repeat more successfully by recruiting more subjects with fully training and applying different odor compounds to investigate odorants interactions in tertiary mixtures. The results indicated odor perception is not a linear process in tertiary mixtures