• The Korean Journal of Food And Nutrition
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• v.15 no.3
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• pp.241-249
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• 2002

In this research, we targeted to see if there was difference of shelf$.$lives of two different species cucumber. We pickled domestic and exporting cucumber to make comparison while they were fermented and stored. As for the domestic cucumber we choose CHICHEONG and for the exporting cucumber we choose special BAEKSEONG and SHARP 1. We blanched them and soaked them into hot saline water for 8 hours. Two kinds of Cucumber Kimchi were at room temperature for first day and 5'c from 2nd to 28th day. It was found, from the results, that all of samples of pH reached at 3.5 $\pm$ 0.1 on the 14th day of fermentation. The titratable acidity of the control increased on 14th day of fermentation, which was bit late than change of others. The reducing sugar contents of the control did not decrease until 7th day of fermentation while reducing sugar contents of others decreased gradually from the beginning. The patterns of Microfloral changes of two kinds of Cucumber Kimchi were similar during fermentation period. The number of total cell increased up to 14th day, similary the numbers of lactic acid bacteria increased up to 14th day then barely decreased. The hardness of the control was bit higher than others when it was measured on 14th day of fermentation. The sensory evaluation of Cucumber Kimchi with different species showed that both species had siginificant high negative scores in green color and crispness when those were compared between fermentation time and samples.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.981-988
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• 2008

This study was conducted to develop functional black soy sauce with (S2) and without (S3) an outer skin and then compare these products to a control soy sauce (S1). In addition, the effects of different fermentation periods on the pH, buffering power, titratable acidity, total acidity, salt content, and browning and Lab value were evaluated. Furthermore, the antioxidative activities of the black soy sauce were compared to those of the control soy sauce based on the total phenolic compounds and free radical scavenging activity, including the 1,1-diphenyl-2-picryl-hydrazil (DPPH) scavenging activity and the thiobarbituric acid value (TBA value). The pH and buffering power of S2 were lower than of S1 and S3, while the titratable acidity and total acidity were higher. The salt content of all samples decreased after 60 days of fermentation, after which it increased slightly for up to 180 days. Additionally, the browning intensity of all samples increased as the fermentation periods increased, with the browning intensity at 420 nm of S1 being the highest followed by S3 and S2. After 150 days of fermentation, the L value of S1 was higher than that of S2 and S3, but the while a value of S2 was higher than those of S1 and S3 and was increased as the fermentation periods. Moreover, the b value of S1 was the highest at the end of the fermentation period, followed by the b values of S3 and S2. The amount of total phenolics in S1 was greatest, followed by S2 and S1. Conversely, the DPPH radical scavenging activity of S2 was the highest, followed by S3 and S1. Finally, the TBA value increased rapidly from day 30 to day 180 of the fermentation period, and the TBA value of S2 was lower than those of S1 and S3.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.725-732
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• 2015

This study was conducted to evaluate the effects of ethanol on the prolongation of the shelf-life of kimchi paste. Kimchi paste was prepared by adding 0.5~3.0% ethanol, and then stored at $4^{\circ}C$ for 35 days. The retardation of kimchi paste fermentation was evaluated by measuring chemical, microbial, and sensory characteristics. Titratable acidity and pH showed a slight difference, depending on the ethanol concentration. The titratable acidity showed the low content in kimchi paste with 3.0% ethanol during fermentation, whereas the pH showed a reverse tendency, indicating that fermentation was inhibited under a high ethanol concentration. The changes in the sugar-reduced contents were similar to that of the pH. The growth of microorganisms such as total aerobic bacteria, lactic acid bacteria, yeasts and molds in kimchi paste during fermentation were inhibited by ethanol, and the addition of 3.0% ethanol was most effective to inhibit the microbial growth. The number of coliform bacteria was decreased during fermentation of kimchi paste and not detected in any sample at 35 days, except for kimchi paste with 3.0% ethanol. In sensory evaluation, the addition of 0.5~1.5% ethanol in kimchi paste was showed no significant difference on sensory properties compared to the kimchi paste without ethanol (p<0.05). As a result, it is considered that the addition of 1.5% ethanol is the most appropriate to maintain the quality of kimchi paste, without the changing the flavor.

• Korean journal of food and cookery science
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• v.24 no.5
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• pp.573-579
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• 2008

In this study, kimchi containing Styela clava (Korean name: miduduk) was prepared, and the quality of the prepared kimchi was evaluated during 4 weeks of fermentation at $4^{\circ}C$. S. clava was added to salted cabbage at concentrations of 0, 1, 2, and 3%(w/w). The quality characteristics of the kimchi were determined by measuring pH, titratable acidity, salinity, color, and microbial amounts. All kimchi evidenced a rapid decrease in pH until 2 weeks, and then a gradual decline thereafter. Titratable acidity increased gradually until 2 weeks, then sharply increased thereafter. Salinity increased until 3 weeks. We noted only slight overall color differences between the kimchi samples. Total microbial and lactic acid bacterial counts achieved maximum levels at 3 weeks, and the kimchi to which 1 and 2% S. clava was added evidenced values higher than that of the controls. In our sensory evaluations, the kimchi to which 2% S. clava was added was scored highest in terms of color, flavor, and overall acceptance.

• Food Engineering Progress
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• v.14 no.4
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• pp.346-353
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• 2010

Due to the globalization of Korean foods, there are great interests in traditional Korean foods. Thus, the enhancement and development of makgeolli processing have been constantly accomplished. In case of makgeolli, the storage stability is very important because the fermentation of makgeolli during distribution is still progressed. Therefore, the objective of this study was to investigate storage stability of makgeolli by separation storage methods. During the 30-day storage at $10^{\circ}C$, pH value, titratable acidity, color value, sugar content, reducing sugar content, and alcohol content were measured. Microbial cell counts were also evaluated. Reducing sugar content was decreased after 10 days for all the samples. In the case of titratable acidity and color, these values were constantly increased with storage time. Especially, the yellowness value of the precipitate of makgeolli was increased by two times than that of the beginning. There was a decreasing tendency for lactic acid bacteria with storage time. In case of yeast, there was a decreasing tendency after 15 days, but the significance was not detected. The quality changes in the samples from centrifugal separation were relatively less than the control. Therefore, the separation storage method could affect the enhancement of makgeolli quality during distribution.

• Korean Journal of Food Science and Technology
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• v.51 no.1
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• pp.35-41
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• 2019

The sensory characteristics of eight commercial ready-to-drink (RTD) cold brew coffees were compared by descriptive analysis. The cold brew coffee samples were analyzed for hunter color values, brown color, turbidity, pH, titratable acidity, soluble solids, total phenolic content, and chlorogenic acid content. Three appearances, nine aroma, five flavor/taste, and four texture/mouth-feel related sensory attributes were evaluated by a panel of nine judges. The results of three-way analysis of variance of descriptive data showed that all sensory attributes except "fruit" aroma, "dark chocolate" aroma, "bitter" aroma, and "sweet" taste had significant differences among the samples (p<0.05). Based on the principal component analysis (PCA) of the descriptive data, the samples were primarily separated by first and second principal components, which accounted for 81.78% of the total variance among the samples with high intensities of "nutty aroma", "grain aroma", and "grain taste" versus "earth aroma", "sour aroma", "sour taste", "astringent", "smoothness", and "residual". In the correlation analysis of sensory terms and physicochemical parameters, titratable acidity and soluble solids showed significant positive correlations with earth aroma and smoothness characteristics.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.227-235
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• 2015

The objective of this study was to improve the quality of Korean rice wine with wild type yeast strains isolated from various traditional Korean fermented foods. Herein the fermentation and sensory characterization of wild yeast, for the purposes of brewing Korean rice wine, was investigated. 12 yeast strains were examined for their ethanol and glucose tolerance. In addition, the pH, soluble solids, acidity, amino acidity, ethanol content, organic acids, and volatile compounds were also studied for the alcoholic beverages made with the wild yeasts. Almost all Saccharomyces genera yeasts were showed to have a tolerance at 10% ethanol, but non-Saccharomyces genera yeasts displayed a low tolerance. The alcoholic beverages fermented by non-Saccharomyces yeasts demonstrated higher levels of soluble solids, titratable acidity, amino acids, and lower ethanol content, when compared with the alcoholic beverages fermented by Saccharomyces genera yeasts. The organic acid content, such as malic acid, acetic acid, and succinic acid, was seen to also be higher. The electronic nose was analyzed, and discriminant function analysis (DFA) was used for discriminating wild yeast strains. The DFA plots indicated a significant separation of Saccharomyces genera and non-Saccharomyces yeast strains. For volatile compounds, ethyl acetate from non-Saccharomyces yeasts, and ethanol from Saccharomyces genera yeast, a high area ratio was observed.

• Journal of Dairy Science and Biotechnology
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• v.37 no.4
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• pp.237-246
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• 2019

In this study, quality characteristics of yogurt supplemented with Angelica gigas Nakai leaf extract were examined. The pH of the yogurt ranged from 4.40 to 4.45 and the titratable acidity ranged from 0.96% to 0.98%. The viscosity tended to decrease with the addition of the Angelica gigas Nakai leaf extract, but did not affect stability during storage. In the range of 0.1% to 0.3%, lactic acid bacteria were present in the range of 1.9×10⁹ to 3.2×10⁹ CFU/mL. The decursin content in yogurt was quantitatively analyzed, depending on the addition of 0.1% to 0.3% of Angelica gigas Nakai leaf extract and was found to be 0.26 ㎍/g, 15.23 ㎍/g, and 23.57 ㎍/g respectively. Organic acid showed the highest generation of lactic acid. The antioxidant properties of yogurt were shown to increase with the addition of the Angelica gigas Nakai leaf extract. The sensory score of yogurt supplemented with 0.1% of the Angelica gigas Nakai leaf extract was highly valued, at a level similar to that of plain yogurt. Yogurt supplemented with 0.2% of the extract was rated above the normal score of 6.31 to 6.50. As shown by the results, the optimal concentration of Angelica gigas Nakai leaf extract for addition to yogurt was within 0.2%.

• Journal of Nutrition and Health
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• v.14 no.4
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• pp.175-181
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• 1981

This study was carried out to investigate the feasibility of production of soy yogurt, which is inexpensive and high protein product with an acceptable flavor, from soy milk using lactic acid bacteria. Utilization of various carbohydrates by Lactobacillus acidophilus, Streptococcus thermophilus and Lactobacillus bulgaricus was stuied. Sucrose, the major carbohydrate in soymilk, was fermented by L. acidophilus and S. thermophilus. None of the testing microorganisms was able to ferment melibiose and raffinose. Growth of lactic acid bacteria in soymilk was examined every 4 hour. L. acidophilus exhibited the highest growth rate during the early stage. After 16 hours of incubation, however, all the cultures with the exception of L. bulgaricus grew at nearly equal rates. Microscopic examination of mixed cultures showed that the presence of S. thermophilus was much more pronounced than that of L. bulgaricus. All the cultures with the exception of L. bulgaricus formed acid rapidly during 16 hours of incubation, bringing the titratable acidity to 0.6% and pH to 4.3, which was sufficient to cause coagulation of soymilk. L. bulgaricus produced acid to a much lesser extent and caused coagulation of soymitk after 30 hours at earliest. Three kinds of yogurts were prepared from 100% soymilk, 100% milk and 50% soy-50% milk combination by S. thermophilus and were evaluated by taste panel. Soy yogurt received a significantly lower mean odor score than milk yogurt. Soy yogurt had custardlike texture, while milk yogurt was syrupy. However the scores for texture as well as those for color and flavor did not differ significantly among the treatment. The mean total scores for yogurts were not significantly different and were equivalent to ratings between good and high fair.

• Food Science and Preservation
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• v.15 no.2
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• pp.311-316
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• 2008

We studied changes in a high-proof maesil liqueur during a 5 month leaching and ripening period at $10^{\circ}C,\;20^{\circ}C$, and $30^{\circ}C$. Titratable acidity increased after 2 months at all temperatures, but pH only changed after 2 months at $30^{\circ}C$. The absorbance at 420 nm increased significantly during a high temperature leaching and ripening period. The alcohol concentration was similar for maesil liqueurs held at $10^{\circ}C$ and $20^{\circ}C$ for 2 months. The levels of reducing sugars and polyphenols were also higher for liqueurs stored at higher temperatures. The major free sugars present after one month (in order of decreasing concentration) were fructose, glucose, sucrose, and maltose. The major organic acids were citric, lactic, malic, succinic and acetic acid The total organic acid content of maesil liqueur decreased after 1 month at $10^{\circ}C$ but increased until 2 months at $20^{\circ}C$ and $30^{\circ}C$.