• Journal of Life Science
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• v.26 no.11
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• pp.1298-1307
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• 2016

In the study, we investigated the optimum fermentation conditions as well as changes of physicochemical and antioxidant characteristics during the fermentation of jujube wine. The physicochemical characteristics of the jujube hot water extracts used in this study were a pH of 5.05, 0.01% acidity, and $6.5^{\circ}Brix$ concentration. For jujube wine fermentation, the optimal fermentation strain was selected among the isolated strains and the final chosen strain was identified as Saccharomyces cerevisiae, based on the 26S rRNA gene sequencing and similarity searching in GenBank DB. The jujube wine fermented with an initial $15^{\circ}Brix$ concentration of jujube extracts showed a maximum alcohol content of 13% and lower residual sugar concentration. Alcohol content during the jujube wine fermentation was increased after 3 days of fermentation, and no significantly difference after 6 days was found. The residual sugar concentration during the fermentation periods was significantly decreased with increasing alcohol content. The jujube wine properties at 12 days of fermentation were as follows: a pH of 4.34, acidity of 0.29%, alcohol content of 12.8%, and a residual sugar concentration of $8.70^{\circ}Brix$. The malic acid content in the organic acid of fermented jujube wine was significantly decreased during the fermentation proceeding, whereas the succinic acid and lactic acid contents were significantly increased. Antioxidant characteristics of the fermented jujube wine were appeared ABTS radical scavenging activity 45.80%, DPPH radical scavenging activity 61.89%, nitrite scavenging activity 91.95% and total polyphenol compound 3.69 mg/ml. In terms of consumer liking of the jujube wine by sensory evaluation, the color and overall acceptability of jujube wine were evaluated as more than average.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1523-1528
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• 1999

The consumer's demands for minimally processed fruits and vegetables have been increased rapidly because of its convenient handling, fresh-like quality as well as producing less wastes from the environmental point of view. Asian pears which are one of the main fruits widely produced and consumed in Korea easily lost their characteristics due to browning and softening after cutting. The objective of this study is to investigate the effects of various treatments on delaying deterioration of sliced Asian pears. 'Shingo' pear slices were treated with various solutions $(1%\;NaCl,\;0.2%\;L-cysteine,\;1%\;CaCl_2\;or\;1%\;calcium\;lactate)$ and were packaged with low density polyethylene $(LDPE,\;60\;{\mu}m)$, ceramic $(CE,\;60\;{\mu}m)$ or vacuum $(Ny/PE,\;80\;{\mu}m)$ film at $20^{\circ}C\;and\;0^{\circ}C$. In order to evaluate the quality of packaged sliced pears, quality index was determined in terms of color, firmness, soluble solids, titratable acidity. ascorbic acid, changes of gas composition, microbial test, and sensory quality. The results showed that sliced 'Shingo' pears packaged with CE and vacuum film maintained better quality than with LDPE at $0^{\circ}C\;and\;20^{\circ}C$. To retard browning and softening. 0.2% L-cysteine and 1% NaCl solutions applied for 1 minute were effective to reduce surface browning of sliced pears, and 1% $CaCl_2$ was the most effective to prevent softening.

• Journal of Life Science
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• v.25 no.5
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• pp.557-567
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• 2015

To increase the marketability of Dolsan leaf mustard Kimchi, seasonings were prepared by sea tangle and Lentinus edodes. Gat Kimchi A (GK-A) and Gat Kimchi B (GK-B) were prepared by addition of complex seasoning with Sea tangle (CSS), complex seasoning with Lentinus edodes (CSL), respectively and evaluated the quality characteristics. GK-A contained high minerals and dietary fiber and showed the effect of delaying pH-lowering and acidity-rising. There were no significant differences in salinity test after 70 days. Reducing sugar of test groups was higher than control. During the fermentation, Leuconostoc sp. was grown in GK-A and GK-B than control. Growth of control's Lactobacillus sp. increased 20 days after. Up to 30 days, lightness of control was high. Yellowness were increased browning potential in GK-B, 20 days after. From the initial to 10 days, Hardness of GK-A showed higher than the others. glutamic acid and aspartic acid content of GK-A was higher significantly than the others in the entire fermentation period (p<0.05). At 0, 10, 30 days, sweet-tasty amino acids of GK-A showed a significantly higher level than the others (p<0.05). From 10 days to 40 days of fermentation, the sensory evaluation of GK-A is better than the other groups. Comprehensively reviewed the above results, the conclusion is as follows: CSS made with sea tangle as a main ingredient. GK-A by seasoning the CSS to 90 g GK-A is expected as a new Dolsan leaf mustard products that can provide flavor and nutrition to the consumer at the same time.