• Food Science and Biotechnology
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• v.16 no.4
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• pp.526-530
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• 2007

The objective of this study was to establish the optimum alcohol fermenting conditions for the processing of kiwi wine and vinegar products. Six yeast strains were examined for their alcohol production from kiwi at $30^{\circ}C$ for 72 hr with continuous shaking at 100 rpm. Under these conditions, Saccharomyces kluyveri DJ97 produced the highest alcohol content of 10.2%. As the fermentation time extended to 96 hr, the alcohol content reached a maximum of 12.75%. The optimum alcohol fermenting conditions for kiwi fruit were accomplished when kiwi was added to an equal amount of water, inoculated with S. kluyveri DJ97 and fermented at $30^{\circ}C$ for 96 hr with continuous shaking. The content of soluble solids decreased as the alcohol concentration increased, whereas little change was observed in the pH and titratable acidity during the low temperature aging process. Other alcoholic compounds, such as methanol, isopropanol, n-propanol, isobutanol, and isoamylalcohol, tended to increase as fermentation progressed.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.56-62
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• 1995

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang meju during fermentation for 60 days. The pH of meju decreased continously up to 40 days of aging and then increased slightly thereafter, while the change in titratable acidity showed the opposite trend to that of pH. The viable cell count of aerobic bacteria increared gradually for up to 40 days of fermentation and then decreased slightly thereafter, while that of molds and yeasts showed a rapid increase up to 40 days of fermentation and then leveled off. ${\alpha}-amylase$ activity increased slightly for up to 40 days of meju fermentation and then stabilized. On the other hand, ${\beta}-amylase$ and glucoamylase activities did not show a significant change for up to 20 days of fermentation and then increased rapidly at 40th day of fermentation. Acidic, neutral and alkaline protease activities increased sharply up to 40 days of aging and then decreased significently at 60th day of fermentation. These results suggest that meju fermented for 40 days had the highest quality in terms of the number of microflora and enzyme activity.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.1-9
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• 2017

Instant hot sauce was prepared to produce a similar product to Korean-style gochujang using different ratio of cheongguk-jang (0~20%) and red pepper powder (7~27%). Moisture content decreased from 43.21 (control: BS0) to 19.13%(maximum addition of cheongguk-jang: BS4). L value was the lowest with control (BS0), and a-value and the b-value were higher with BS4. pH tended to increase significantly as the addition amount of cheongguk-jang powder increased (p<0.001). Titratable acidity was lowest at 5.40 for BS0 and 6.30 for BS4. Salinity and soluble solids were also decreased but viscosity increased with addition of cheongguk-jang. DPPH radical scavenging activity was increased from 50.9% (BS0) to 77.6% with BS4. Overall preference was highly evaluated with the sample (BS3) prepared with red pepper, cheongguk-jang, japanese apricot extract, and water at 12, 15, 40 and 25% (w/w), respectively. Results showed that the instant hot sauce had a possibility to replace Korean-style gochujang requiring lengthy fermentation time.

• Food Science and Preservation
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• v.6 no.3
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• pp.339-344
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• 1999

The effects of water extracts of cow bone(WECB), and crab-shell powders(CSP) on the fermentation of kimchi were investigated. WECB has not a great effects on pH, titratable acidity, ratio of lactic acid bacteria against total microbe, and the number of Leuconostoc and Lactobacilli, but has on sour taste, and flavor and overall taste. The kimchi prepared by adding the 0.03% WECB and 1.5% CSP together showed more effective than the control and CSP-added kimchi in pH maintenance, buffer action ratio of lactic acid bacteria against total microbe. The sensory profiles such as fishy and garlic flavor, crispness and overall taste showed in the control and CSP-added kimchi were improved in the kimchi added no only, and CSP and WECB together.

• Food Science and Preservation
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• v.7 no.1
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• pp.29-32
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• 2000

Storage life of grape cultivars including Kyoho(Inzuka), which were imported from Japan and are cultivated after adoption as farming application, were examined. The stu요 was accomplished with grapes packed by PE film under storage temperature $0^{\circ}C$ and humidity 90%RH loss of weight, Weight loss and occurrence of abnormal fruit increased in proportion to storage days. Abnormal fruits of Kyoho(izuka), North Black , and Seto giants increased rapidly after 60 days of storage, resulting in slight deterioration of commercial value. Similarly, this phenomenon of Campbell early , Takasumi , and Aki Queen occurred after 70 days of storage. External appearance decreased rapidly after 60 days of storage, resulting in 7.0 index of Takatsuma and Aki Queen , 3.0-3.6 of North Black and Seto Giants, and 5.0 of Campbell Early, kyoho (izuka0, and takasumi after 80 days of storage. Soluble solide content and titratable acidity showed a trend to be decreased with lapse of storage. Sugar/acid ratio shwoed much fluctuation between different grapes. Possible storage days, in view of more 70% merchandise berry ratio, were 90 days of Takatsuma and Aki Queen , 70 days of Campbell Early, 60 days of Takasumi , kyoho(Iizuka), and Seto giants, below 60 days of North Black.

• The Korean Journal of Food And Nutrition
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• v.21 no.2
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• pp.135-142
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• 2008

This study investigated to develop new functional yogurt added domestic yuza(Citrus junos). In order to make the most effective yogurt, yuza extract and fructose were mixed at different proportions. DPPH free radical scavenging activity of yuza yogurts increased dependent on concentration. The results of the DPPH free radical scavenging activity, the 1% yuza yogurt was proven to be the best. The overall sensory score for yogurt made from adding 1% yuza ethanol extract was the best of tested yogurts. The antioxidant activity(DPPH free radical scavenging activity) was the highest in 1% yuza yogurt. The quality characteristics of prepared yogurt were evaluated in terms of acid production(pH and titratable acidity), viscosity, color and levels of lactic acid bacteria during storage period. During storage, the quality of yogurt made from adding yuza extract was better than control(without yuza extract). The sedimentation of curd was repressed a little by adding 1% yuza extract.

• Food Science and Biotechnology
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• v.15 no.1
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• pp.13-18
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• 2006

Mandarin juice was processed using a continuous high pressure $CO_2$ system. Response surface methodology was used to investigate the effects of the processing parameters such as temperature, pressure, residence time, and %(w/w) ratio of $CO_2$ to juice on total aerobic count (TAC), pectinesterase (PE) activity, cloud level, $^{\circ}Brix$, pH, and titratable acidity (TA) of the juices. Maximum log reduction (3.47) of TAC was observed at $35^{\circ}C$, 41.1 MPa, 9 min residence time, and 7% $CO_2$. PE was inactivated by 7-51%. The cloud was not only retained but was also enhanced by 38%. Lightness and yellowness increased, and redness decreased. The processing temperature and % $CO_2$/juice ratio significantly affected high pressure $CO_2$ processing of the juice in terms of pasteurization, PE inactivation, cloud increase, and color change. The $^{\circ}Brix$, pH, and TA before and after treatment remained unchanged.

• Journal of Microbiology and Biotechnology
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• v.6 no.1
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• pp.50-53
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• 1996

A cultured milk product was made by fennenting 10$\%$ reconstituted skim milk with Lactococcus lactis subsp. lactis TA29 and Saccharomyces exiguus SK2. L. lactis TA29 and S. exiguus SK2 grew up to 1.0 $\times 10^9\;and\;2.0 \times 10^6$ cfu/ml, respectively. After the fermentation 21$\%$ of lactose was hydrolyzed, pH was lowered to 4.2, and titratable acidity and alcohol concentration were increased to 0.96 and 0.023$\%$, respectively. When the fermented milk was stored at $4{\circ}C$ for 9 days, the viable cell counts for L. lactis TA29 and S. exiguus SK2 were $6.5 \times 10^5\;and\;1.6 \times 10^6$ cfu/rnl, respectively. The alcoholic fermented milk prepared in this experiment was more inhibitory against some pathogenic bacteria including C. perfringens than commercial yoghurt products tested.

• Preventive Nutrition and Food Science
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• v.13 no.2
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• pp.117-121
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• 2008

The effects of water dropwort on the physical characteristics of tofu were investigated and consumer acceptance test was conducted. pH decreased significantly with increasing water dropwort concentration from 0 to 3%, whereas titratable acidity showed the reverse trend (p<0.05). The amount of water dropwort did not significantly influence the moisture content up to 2% substitution (p>0.05). Turbidity increased significantly with increasing water dropwort concentration (p<0.05). A significantly lower moisture content in 3% water dropwort tofu may be attributed to the denser structure and hardness of that was significantly higher than those of the other samples (p<0.05). Even though $a^*$-values of 3% water dropwort tofu was lower than that of control, $a^*$-values increased significantly with increasing water dropwort content (p<0.05). On the contrary, $b^*$-values decreased significantly with increasing water dropwort content (p<0.05). 2% water dropwort tofu was found to be the best with respect to its overall acceptability score.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.1
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• pp.30-34
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• 2000

Salted Chinese cabbage was washed in 1,000 ppm solutions of grapefruit seed extract(GFSE) or citric acid, and used to make kimchi for the retentio of quality characteristics during fermentation at $10^{\circ}C$. Kimchi treated with GFSE or citric acid showed a retarded increase in titratable acidity and decrease in pH and reducing sugar content. Total microbial count and lactic acid bacteria of GFSE treated kimchi were about 1.1 log(CFU/g) lower than those of control and citric acid treated kimchi after making, but the difference was gradually reduced during fermentation.