| Summary: | 碩士 === 東吳大學 === 微生物學系 === 85 === Shaohsing wine is a kind of qu-brewed wine as well as one
of the popular alcooholic prooduct on the local market. Except
part off it,s qu is made from wheat, the rest materials are all
belong to polished rice. Therefore, the quality off the rice
affect the final wine product exte-nsively. The nutritious
constitutents such as protein and fat are higher in the bran
of brown rice. The amino acids of protein contribute the typical
flavor and taste of shaohsing wine, but the unsaturated fatty
acids and some impurties have negative effects on the wine
quality. Generally, all of these constitutents have been reduced
by using the polished rice. How to remove the unwanted material
from the grain and in the mean time keep the protein remain in
the rice is a very interesting topic.
The super critical carbon dioxide (SC-CO2) has been used
successffully as a kind of extraction solvent in food industry
for many years. The present study is using the SC-CO2 defatted
materials for making Shaohsing wine which may have the following
advantages: (1) the protein cannot be extracted out by SC-CO2,
(2) the solubility of unsaturated fatty acid is higher than that
of the saturated fatty acid in SC-CO2, (3) less loss than
polished rice.
The oil off the rice grains and the wheat grists have been
continuous extracted with mobile super critical car-bon dioxide
fluid at the temperature of 40℃, 50℃, 60℃ and the pressure
of 4000, 4500, 5000 psig. The most suitable extraction condition
for brown waxy rice, brown Pon-Lai rice and wheat grists are
all found at 60℃ and 4500 psig. The total amount of oil
extracted, oil solubility, oil content and saturation degree
for the defatted brown waxy rice are 0.3147g, 0.147g/l, 2.23
﹪and 0.375; for the defatted brown Pon-Lai rice are 0.4283g,
0.2006g/l, 3.38﹪and 0.224; for the defatted wheat grists are
1.0206g, 0.4780g/l, 1.27﹪and 0.233.
The defatted wheat have been used for wheat qu preparation,
the α-amylase and glucoamylase activity are lower to 20∼30
﹪, while the acid protease and acid carboxypeptidase activity
are higher to 30∼50﹪when compared with undefatted wheat qu.
Lower in enzyme act-ivities of defatted polished rice qu, and
higher enzyme activities in defatted brown rice qu have also
been observed.
The alcohol fermentation is inhibited by using defat-ted
brown rice but not for defatted polished rice. Using
the defatted wheat bran qu for Shaohsing wine making can
increase the color intensity up to 50∼70﹪.
The effect of using the defatted materials for the volatile
flavor compounds of Shaohsing wine have been analyzed by GC.
The lower in n-propanol and ethyl lactate content, and higher
in ethyl caprate, ethyl paltimate and total ester content have
been observed.
Sensory tests have been carried by using the Berverage
Testing Institute 14-point hedonic scale. The evaluation result
is statistically analyzed by Krammer ranking test. Although no
significant result (5﹪level) was obtained by using the
defatted material,but from the order of the preference sequence,
better results can be obtained by using the defatted wheat qu
or defatted wheat bran qu for making the Shaohsing wine.
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