a two-line flow-injection system using enzyme sensors
for putrecine and hypoxanthine was developed recently
for monitoring the aging process of meat. This system
is far more practical for the quality control of meat
freshness than the conventional methods. However,
even this system, is based on a destructive analysis of
the chemical components produced in meat. It has
been shown recently that the gaseous components evaporating
from food can be a good measure for judging
food quality. For example, a semiconductor gas sensor
sensitive to a particular flavour component from consomme
soup has been developed for evaluating soup
quality [1,2]. The use of a gas sensor can provide a
non-destructive, non-contact method of food analysis,
and would be highly desirable for quality control in
the food industry. On this background, we have explored
the possibility of the gas-sensor-based quality control
of meat freshness. As a first step of the exploration,
the volatile components produced in meat under constant
storage conditions were analysed as a function
of storage time by means of GC-MS analysis based
on a purge and trap technique [3]. As a result, ethyl
acetate was found to be a typical major product at the
initial stage of bacterial putrefaction. This paper deals
with the development of a semiconductor gas sensor
for ethyl acetate vapour as well as its applicability for