Characteristic Aroma Components of the Volatile Oil of Yellow Keaw Mango Fruits Determined by Limited Odor Unit Method

Abstract

Odor detection thresholds of optically active compounds and other volatile compounds found in the oil of yellow Keaw mangoes were determined. Odor intensity of individual components was evaluated by Lod (limited odor unit) based on data of the odor detection threshold and the concentration of individual components at the recognition threshold level of the volatile oils. β-Damascenone and terpinolene were found to have Lod values greater than one and were identified as the components most responsible for the characteristic aroma. Odor recognition threshold of a mixture of 15 chemicals having larger Lod values against natural Keaw mango oils was 1.8 ppm, which exceeded that of Keaw mango oils (0.62 ppm) against Ok-rong mango oils. The mixture of fifteen compounds comprising β-damascenone, terpinolene, ethyl hexanoate, (E,Z)-(2,6)-nonadienal, 2,5-dimethyl-4-methoxy-3(2H)-furanone, (3R)-(-)-linalool, ethyl butyrate, ethyl octanoate, ethanol, (1S)-(+)-δ-3-carene, (1S,5S)-(-)-α-pinene, trans-linalool oxide, (3S)-(+)-linalool, butyric acid, and p-methylacetophenone was judged to possess an aroma very similar to that of the natural Keaw mango. Thus, these fifteen compounds were the key contributors to the aroma of Keaw mango.