采用顶空-固相微萃取-气质联用法(HS-SPME-GC-MS)分别对新鲜薏米、弱异味薏米和强异味薏米的挥发性成分进行分析,从三种不同异味程度的薏米中共鉴定出79种挥发性成分,新鲜薏米、弱异味薏米和强异味薏米中分别鉴定出47、43和51种挥发性成分,相对百分含量分别为96.14%、98.68%和98.00%。通过对比上述三种不同异味程度的薏米中挥发性成分的种类和含量,同时应用气相色谱-质谱联用结合嗅闻(GC-O-MS),采用气味活度值(OAV)结合气味强度值对强异味薏米中的异味成分进行鉴定。从强异味薏米的挥发性成分中鉴定出12种异味成分,分别为己醛、庚醛、2-庚烯醛、辛醛、反-2-辛烯醛、壬醛、反-2-壬烯醛、癸醛、2-癸烯醛、己酸、2-壬酮和6-十一酮。
To
confirm the substances that make adlay seeds smelly, the volatiles of adlay
seeds (Coix lachryma-jobivar.
ma-yuen Stapf) of three off-flavor levels were studied. For the analysis, the
headspace-solid phase micro-extraction (HS-SPME) method was used in combination
with gas chromatography-mass spectrometry (GC-MS) and GC–olfactometry (GC-O),
where the human nose is used as a sensitive and specific detector for
off-flavor compounds. More than 79 of volatile compounds which belonged to
distinct chemical families were analysed. A total of 47, 43 and 51 volatile
compounds were identified in fresh, faintly smelly and strongly smelly adlay
seeds with total relative contents of 96.14%, 98.68% and 98.00%, respectively. Meanwhile,
12 kinds of off-flavor active compounds were detected from the strong smelly
adlay seed volatiles by GC-O and odor activity value method (OAV), including hexanal,
heptanal, 2-heptenal, n-octanal, (E)-2-octenal,
1-nonanal, (E)-2-nonenal, decanal,
2-decenal, hexanoic acid, 2-nonanone and 6-undecanone.