An octadecyl sorbent column was selected for solid phase extraction of
volatile components of soymilk. The volatiles thus adsorbed were elut
ed with a mixture of hexane and diethyl ether (3:1 v/v) and then appli
ed directly to GC column. The detection limit of the method was 0.1 pp
m for both hexanal and hexanol. Total content of these two compounds i
n soymilk was linearly correlated to the lipoxygenase activity in soyb
eans. Data points on principal component similarity (PCS) scattergrams
for soymilk samples were grouped toward two directions depending on t
he grit size of ground beans heated by microwave. Sensory panels detec
ted beany flavour in these samples but without distinction between the
se two types of GC patterns as classified on the PCS scattergram. Prin
cipal components 1 (PCI) and 2 (PC2) had high loadings of pentanol and
hexanal and hexanol and hexanal, respectively. Pentanol was produced
upon heating finely ground soybeans. (C) 1998 Canadian Institute of Fo
od Science and Technology. Published by Elsevier Science Ltd. All righ
ts reserved.