ODOR THRESHOLDS OF VARIOUS UNSATURATED BRANCHED ESTERS

A series of unsaturated branched esters were purified by preparative g as chromatography and their odor thresholds were determined using sens ory panel methods. In general, unsaturated branched esters had higher odor thresholds than their saturated counterparts. Double bond positio n and configuration had marked influences on the odor threshold. In mo st cases the addition of a double bond in the C-2 position of the acid resulted in significantly higher odor thresholds while the addition o f a double bond in positions further away from the acid carbonyl had a smaller effect on the odor threshold. Ethyl 2-methyl-4-pentenoate had the lowest odor threshold (0.01 mu L/10(3) L) of the esters tested wh ile methyl (E)-2-methyl-2-butenoate (methyl tiglate; 130 mu L/10(3) L) had the highest odor threshold.