Application of Gc-O, Aroma Recombination and Omission Tests To Identify Horse Urine-Like Off-Odor in Gastrodia elata Blume
Abstract
Gastrodia elata Blume is a nutritious ingredient with high edible value. However, its distinctive odor, "horse urine-like off-odor", has limited its applications. The potential unpleasant odorants presenting a horse urine-like off-odor in G. elata was investigated by GC-MS-O. Two G. elata samples, one cultivated in Yichang (YC, with horse urine-like off-odor) and the other one cultivated in Yingshan (YS, without off-odor), were used for chemical analysis and sensory evaluation. The identification of compounds responsible for the odor differences between YC and YS provided the basis for determining key odorants that contribute to horse urine-like off-odor. In the GC-O analysis, 37 aroma compounds were identified in YC while 32 in YS. Aroma recombination and omission tests proved that ten compounds (including pentanal, benzeneacetic acid, benzaldehyde, 2,3-butanedione, acetoin, acetic acid, hexanoic acid, p-cresol, m-cresol, and 2-methoxy-4-vinylphenol) were the main contributors to the horse urine-like off-odor. The pathways of off-odor formation in G. elata were elucidated. Our results provide insights into the formation of horse urine-like off-odor in G. elata.
