• Food Science and Preservation
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• v.17 no.2
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• pp.202-207
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• 2010

The effects of ultrasound treatment, in combination with ascorbic acid, on the quality of fresh-cut 'Jonathan' apples was investigated. Prepared apple slices were ultrasonicated in distilled water (US) or in 1%(w/v) ascorbic acid solution (UA) and the other samples were just dipped in 1%(w/v) ascorbic acid solution (AA). All samples were stored at$10^{\circ}C$ for 12 days. UA-treated samples showed high $L^{*}$ and hue values and low $a^{*}$, $b^{*}$, chroma, and ${\Delta}E$ value. Both control and US-treated samples showed considerable browning. A significant inhibition of polyphenol oxidase activity was observed after UA treatment. The level of total phenolics in UA-treated samples was higher on the day of treatment compared with other samples. Total soluble solids, pH, titratable acidity, and gas concentrations were similar in all samples. This study demonstrated that the simultaneous treatment of ultrasound and ascorbic acid was effective in preventing enzymatic browning of fresh-cut 'Jonathan' apples and maintaining total phenolics contents.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.2
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• pp.195-204
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• 1996

This study was conducted to enhance the shelf-life of Kimchi and to make the unique taste of Kimchi by fermentation control. Kimchis, Prepared by win baechu soaked in 10% salt solutions containing 0.2-0.3% organic acids (OS-Kimchi), acetic acid, citric acid (CA-Kimchi), lactic acid, its mixtures and formic acid+acetic acid+fumalic acid+malic acid+citric acid(FAFMC), were examined for pH, titratable acidify, sensory evaluation, the number of total microbe and lactic acid bacteria, content of organic acids and texture during fermentation at 1$0^{\circ}C$. The decrease of pH and the increase in acidity, CA-Kimchi showed lower than those of control and various OS-Kimchi. Total microbe, lactic acid bacteria, content of lactic acid of CA-Kimchi were lower than those of control. The hardness of CA-Kimchi measured instrumentally was higher than that of control. Sensory scores of CA-Kimchi were also lower than those of control, so the Kimchi maintained good crispness and overall taste.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.3
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• pp.408-413
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• 2012

This study aimed to evaluate the physiochemical properties and fermentation qualities of kimchi supplemented with yacon (Smallanthus sonchifolius) during fermentation. Kimchi supplemented with 0%, 0.1%, 0.5%, 1%, and 5% yacon were investigated. As fermentation proceeded, pH decreased from 5.5~5.7 on the first day to 4.6~4.8 on day 21, whilst total titratable acidity (TTA), lactate levels, and number of microbes increased. The kimchi with 5% yacon showed a higher production of lactate concentration at 7 days fermentation than other groups, which is consistent with the observed high numbers of viable Leuconostoc sp. cells at 7 days fermentation. These observations demonstrate that 5% yacon stimulates the growth of kimchi microbes, particularly of Leuconostoc sp..

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.546-560
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• 2013

In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1295-1299
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• 1999

This study was conducted to develop a index for the judgment of suitability of storage conditions by internal gas concentration of 'Fuji' apples under CA storage, and was examined the relationship between the levels of quality characteristics(flesh firmness, titratable acidity and surface green color) and the infernal ethylene and carbon dioxide concentrations of apples. The levels of quality characteristics were not decreased for terms of storage when the infernal ethylene concentration of apples was below 10 ppm, but the levels of quality characteristics were sharply decreased when it was above 10 ppm of Internal ethylene. The high levels of quality characteristics were maintained by the lower internal carbon dioxide concentration of apples, especially at below 2% of internal carbon dioxide. These result showed that the suitable condition for CA storage of 'Fuji' apples was a condition for having below 10 ppm of internal ethylene and below 2% of internal carbon dioxide in apples. The internal ethylene and carbon dioxide concentrations of apples during CA storage can be used as a crucial index for the suitability judgment of storage conditions.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.45-49
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• 2013

This study was carried out to determine a possibility of adding Corni fructus extract (CFE) into yogurt for improving the neutraceutical properties of yogurt and the effects of adding CFE (2~6%, v/v) on the physicochemical and sensory properties of the products during a 15-day storage period at $4^{\circ}C$. Incorporation of CFE into the yogurt samples resulted in a significant pH reduction and a significant increase in titratable acidity. When evaluating the color of the yogurt, the $L^*$-values were not significantly influenced by CFE supplementation; however, the $a^*$- and $b^*$-values significantly increased with the addition of CFE during storage. The power law and Casson models were applied to assess the flow behavior of CFE-added yogurt samples. The magnitudes of apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) for 4~6% CFE yogurt samples were significantly greater than those for the control, indicating that CFE can be used as a thickening agent for yogurt. The sensory test revealed that addition of CFE (2~4%) to yogurt did not significantly affect the overall scores, but the overall preference score for 6% CFE yogurt was significantly decreased. Based on the data obtained from the present study, we concluded that the concentrations (2~4%) of CFE could be used to produce a CFE-added yogurt without the significantly adverse effects on the physicochemical and sensory properties.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1001-1009
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• 2016

This study was conducted to investigate the relationship between quality factors and palatability of modified Doenjang and traditional Doenjang. Fourteen types of Doenjang, including three modified Doenjang and 11 traditional Doenjang samples, were analyzed to evaluate their physicochemical and sensorial properties. There were differences in e-tongue, which indicates overall acceptability. Water contents, minerals, total sugar contents, salt contents, pH, titratable acidity, and free amino acids of Doenjang did not show significant differences. From the correlation and regression analysis, palatability was closely related to the e-tongue sensor such as $X_1$ (sourness), $X_3$ (saltiness), and $X_4$ (umami) to -0.772, -0.642, and 0.678, respectively. The regression equation for sensorial palatability (Y) was Y=$45.356-0.008X_1-0.010X_3$ with a coefficient of 0.882.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.12
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• pp.1805-1812
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• 2012

The effects of red-potato on the physicochemical properties of kochujang were investigated during fermentation. The number of yeast and aerobic bacteria in kochujang increased up to 4 weeks of fermentation, then the yeast number slowly decreased. Amylase activities also increased after 2~4 weeks of fermentation with the addition of red-potato. The Hunter L-value of kochujang decreased sharply and the a-value increased through the addition of starch syrup, causing major changes in total color difference as the ratio of red-potato increased. There was a direct correlation between the amount of red-potato with water activity and titratable acidity. The oxidation-reduction potential of kochujang decreased sharply after 12 weeks of fermentation, and was lowered with the addition of red-potato. As the ratio of red-potato increased, reducing sugars and ethanol contents of kochujang increased in the later stage of fermentation, while the amino-type nitrogen content was lower. Sensory results showed that a final percentage of 2% red-potato in kochujang was optimal for taste and overall acceptability.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.66-77
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• 2016

This study aimed to develop eel dipping sauce adding bokbunja(Rub coreanus Miquel) vinegar and investigated the physicochemical and quality properties of eel dipping sauce for optimization. To accomplish the objective, eel dipping sauce was created by adding bokbunja vinegar. The findings are as follows. Among the composition, moisture and crude fiber content increased as more bokbunja vinegar was added. As for crude protein and crude ash, however, their content decreased as more bokbunja vinegar was added. In terms of crude fat, there was no difference between the control group and addition group. As for pH, the content decreased as more bokbunja vinegar was added. Also. the following properties declined as more bokbunja vinegar was added: titratable acidity; sugar content; salinity; viscosity. In terms of chromaticity, however, the brightness(L), redness(a), and yellowness(b) all increased. The overall acceptability was as follows: 0% < 5% < 10% < 20% < 15% Therefore, the proper content of bokbunja vinegar to add in eel dipping sauce is approximately 15~20%.

• Korean journal of food and cookery science
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• v.6 no.2
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• pp.51-58
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• 1990

Quality deterioration of barley drink during storage was examined by measuring viable count, titratable acidity (TA), turbidity and pH of barley drinks with or without barley particles stored at temperatures of 20, 25, 30, and 35$^{\circ}C$. Qualitative analysis of organic acids in spoiled barley drink was also performed. TA of barley drink during storage increased to 0.009, 0.0095, 0.0097 and 0.020% at 20, 25, 30 and 35$^{\circ}C$, respectively. TA reached the mixima between 7 and 10 days of storage and reduced from then on. pH values followed the exactly reverse trend of TA. The rate of bacterial spoilage of barley drinks was faster when it was stored at higher temperatures. The numbers of bacteria were in the range between 9.0${\times}10^6-8.0{\times}10^8$ cells/ml depending on the storage temperatures and the different brands. Those samples with higher bacterial growths showed higher optical densities. Volatile organic acids such as acetic, formic, propionic, isobutyric, isovaleric acids were detected in addition to ethyl alcohol. Non-volatile organic acids such as pyruvic, lactic, oxalacetic, succinic, fumaric acids were detected. Among them, acetic acids were most important in their quantities. Five different kinds of spoilage bacteria were isolated and identified as Bacillus Licheniformis, Bacillus coagulans, Badillus cirulans, Bacillus stearothermophilus and Bacillus brevis, all of which were found to form endospores.