• Preventive Nutrition and Food Science
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• v.16 no.1
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• pp.74-82
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• 2011

The fermentation and quality characteristics of kimchi, made by adding different types of red pepper (semi-dried red pepper, fresh red pepper, dried red pepper) according to drying conditions, were examined for 15 days at $10^{\circ}C$ fermentation. The initial pH was approximately 5.65~5.72 in all groups, and the pH decreased with increasing fermentation time. The color value of a/b showed the highest in kimchi that made with semi-dried red pepper (SDRP-K). The color value of A remained at the initial level for 9 days, regardless of treatments. The color value had a tendency to decrease after 9 days. The lactic acid bacteria increased rapidly during 6 days of storage, but showed no difference among groups. The initial contents of malic acid and succinic acid were in 3.23~4.52 and 6.12~7.97 mg/mL and decreased during fermentation in all groups. The lactic acid and acetic acid were not contained in the beginning, but increased with increasing fermentation periods. The vitamin C content of SDRP-K was 5.20 mg/g, which was significantly higher compared with kimchi that made with dried red pepper (DRP-K), but which did not show any significant difference to kimchi that made with fresh red pepper (FRP-K). As a result of antioxidant activity in optimally ripened kimchi, both $DPPH^+$ and $ABTS^+$ scavenging activities were higher in SDRP-K than any other groups. As a result of the sensory evaluation, overall acceptability was highest in SDRP-K.

• Food Science and Preservation
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• v.13 no.4
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• pp.457-464
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• 2006

To improve the functional properties of Gochujang, different amount of skipjack cooking broth (l%, 3%, 5%) were added and their physicochemical properties were examined during storage. During fermentation of Gochujang, pH value decreased and titratable acidity increased, regardless of the amount of skipjack cooking broth. Content of amino-nitrogen increased rapidly at 30 day of fermentation from 171.59 mg% for the control to 191.10 mg% for 5% skipjack cooking broth, and then slightly decreased. It increased with the increase of the amount of skipjack cooking broth. Content of reducing sugar had the highest value at 30 day of fermentation, and then slightly decreased During fermentation, $\beta-amylase$ activity showed the highest value at 30 day of fermentation, and then slightly decreased. Free amino acid content increased with the increase of skipjack cooking broth amount Hunter L a, and b values gradually decreased during fermentation of Gochujang. Based on sensory evaluation of Gochujang after 90 days, Gochujang with the addition of skipjack cooking broth was better than the control in terms of taste, color, flavor, and overall.

• Food Science and Preservation
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• v.24 no.5
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• pp.576-584
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• 2017

With the goal of developing a new functional fermentation milk using green tea powder (GP), milk was fermented with direct vat set (DVS) starter culture containing Streptococcus salivarius subsp. thermophilus, Lactobacillus paracasei and L. delbrueckii subsp. bulgaricus. We investigated fermentation characteristics and antioxidative activities of fermented milk supplemented with different concentrations (0.5, 1, 2, 3%) of GP. All samples were evaluated for pH, total acidity, viable cell count, and sugar contents. The pH of all samples decreased during fermentation, and the final pH ranged from 4.35 to 4.51. The acidity increased during fermentation, after the fermentation was completed, the titratable acidity was 0.8 to 1.1%. And viable cell count of all samples increased during fermentation, and the final viable cell count was 8.57 to 8.89 log CFU/mL. The sugar content decreased as the fermentation proceeded and finally reached 12 to $13^{\circ}Brix$. And increasing GP, decreased brightness and increased yellowness. Increasing GP concentration added to milk, improved DPPH free radical scavenging activity and ferric ion reducing activity of fermentation milk. The fermentation milk kept their pH, total acidity and viable cell counts standard of fermentation milk during the storage period at $4^{\circ}C$. These findings confirmed the possibility of development of the novel functional fermentation milk through the investigation of the quality characteristics of the fermentation milk added with GP.

• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.661-668
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• 2008

This study was investigated to determine the conditions for an auto-aging system placed within a kimchi refrigerator for optimal fermentation, as well as the optimal conditions for the prolongation of dongchimi storage time. Various fermentation characteristics of dongchimi stored at different temperatures ($5-23^{\circ}C$) were compared. The pH and acidity of dongchimi associated with the highest levels of overall acceptability were $3.9{\pm}0.1$ and $0.25{\pm}0.05%$, respectively. In order to establish the time point for the conversion of fermentation to storage, dongchimi was fermented at $10^{\circ}C$ or $15^{\circ}C$ until the acidity reached the designated points (0.1, 0.2, and 0.3%), and was then stored at $-1^{\circ}C$ for 1 week. According to the sensory evaluation, the dongchimi acidity of 0.2% fermented at $10^{\circ}C$ evidenced the highest levels of overall acceptability after 1 week of storage among the samples. In conclusion, we suggest conditions of $10^{\circ}C$ and $-2.5{\pm}0.5^{\circ}C$ for the fermentation and storage temperature, respectively, and a dongchimi acidity of 0.2% as an index for the time point for the conversion of fermentation to storage in the kimchi refrigerator.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.785-795
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• 2014

This study was conducted to develop low-salinity Kimchi with acetic acid, starters and fruits added for health and taste. The quality characteristics of the developed Kimchi by storage period and salt concentrations were investigated herein. The effects of salinity and fermentation temperature ($0^{\circ}C$, $5^{\circ}C$) on the quality characteristics of low-salinity Kimchi were investigated through physicochemical and microbiological analysis. The sensory characteristics are shown in the results below. The pH and acidity were quickly changed by higher temperature over longer storage periods, with gradual decrease in the pH accompanied with an increase in acidity. The microbiological analysis revealed increase in the total cell number regardless of the concentration and strain added during the storage period. Finally, test of the overall acceptability with regard to sensory characteristics according to the different strain sets in low-salinity Kimchi showed the average score for smell, salty taste and overall acceptability were highest in the hetero-fermentation strain group.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.6
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• pp.971-976
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• 2002

Effect of storage temperature and packing method on the changes in pH, acidity, the levels of lactic acid bacteria, volume expansion of packages and the colorness during the fermentation of kakdugi (diced radish kimchi) were investigated. The fermentation characteristics were greatly influenced by the temperature. The pH of kakdugi fermented at 15$^{\circ}C$ was 4.10 at 3 days, while the pH of kakdugi fermented at $0^{\circ}C$ was 4.03 at 18 days. The acidity of kakdugi fermented at $0^{\circ}C$ very slowly increased compared to that of the kakdugi fermented at 15$^{\circ}C$, 1$0^{\circ}C$ or 5$^{\circ}C$. The required days to reach the acidity of 0.6% (optimally ripened state) were 6 days at 15$^{\circ}C$, 7 days at 1$0^{\circ}C$, 18 days at 5$^{\circ}C$ and 30 days at $0^{\circ}C$. Despite of different fermentation temperature, the numbers of Leuconostoc sp. in optimally ripened kakdugi were similar. However, Lactobacillus sp. in kakdugi fermented at $0^{\circ}C$ was the smallest in number. Also, the volume expansion of aluminum pack was the lowest in kakdugi fermented at $0^{\circ}C$. Both pH and acidity of the kakdugi fermented in different packing condition did not show any difference at 1$0^{\circ}C$ for 20 days, however, the color of the kakdugi was affected by a packing method. Aluminium laminate package in which Ca(OH)$_2$ Pack stuck inside resulted in decolorization of kakdugi compared with aluminum package without Ca(OH)$_2$ pack or plastic jar. It showed the lowest redness and the highest lightness and yellowness. These results indicated that fermentation at $0^{\circ}C$ could increase storage period of kakdugi with minimum growth of Lactobacillus sp., and plastic jar might relieve the problem of volume expansion and decolorization of kakdugi.

• Korean journal of food and cookery science
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• v.13 no.2
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• pp.92-98
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• 1997

Ethyl carbamate is an animal carcinogen and a by-product of fermentation. Since the highest level of ethyl carbamate was found in a traditional soy sauce sample in the previous study, soysauce was prepared in varying experimental conditions with three kinds of meju originated from different area of the country to investigate the factors affecting ethyl carbamate formation. The sample analysis methods included a semi-purification with solid-phase extraction and detection by GC-MS at SIM mode using m/z 62 fragment ion. Among the investigated factors, which includes source meju, bringing length, salt content, irradiation of visible light during bringing or storage, and storage length, source meju and storage length showed most profound effect on the formation of ethyl carbamate. Irradiation of visible light for 12 hours a day during storage lowered the concentration of ethyl carbamate compared to the soysauce kept in the dark. Meanwhile irradiation during the bringing as well as the degree of salt contents showed no effect.

• Korean journal of food and cookery science
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• v.27 no.5
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• pp.507-522
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• 2011

In this study, samples of wheat flour and dough were prepared by adding of 1, 3, or 5% branched dextrin, which is produced from the amylopectin of waxy corn starch using a cyclization reaction with a branching enzyme. The samples were then evaluated qualitatively in terms of farinogram, viscogram, and extensogram characteristics. The fermentation power of dough expansion, extensogram characteristics, specific volume, baking loss, external/internal surface appearance, and sensory qualities were also examined after 4 weeks of storage at -20$^{\circ}C$ to determine the effect on freeze-thaw stability and quality improvement of branched dextrins in the soft roll bread formulation. Furthermore, the samples along with a control were compared regarding their quality characteristics, including changes in moisture content, water activity, color, and textural characteristics during a storage period of 4 days at 20$^{\circ}C$ to determine the effect on preventing retrogradation of the branched dextrin. As the branched dextrin content increased, area and extensibility increased, whereas water absorption, fermentation power of dough expansion, resistance/extensibility ratio, baking loss, and brownness of the crust decreased. However, the control group presented significantly higher peak viscosity, resistance, specific volume, taste, overall acceptability, moisture content, water activity, springiness, cohesiveness, and resilience values than those of the branched dextrin samples, whereas lightness, hardness, and chewiness showed the reverse effect. As the storage period increased, lightness, hardness, and chewiness increased, whereas cohesiveness decreased. In conclusion, the results indicate that adding 1~3% branched dextrin into a soft roll bread formulation from frozen dough had no positive effect on freeze-thaw stability or preventing retrogradation but may provide good nutritional properties.

• Journal of the Korean Society of Food Culture
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• v.11 no.2
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• pp.207-215
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• 1996

This study was carried out to find the effects of salt and other materials on the taste and fermentation of kimchi. Several parameters such as pH, acidity, salt concentration and sensory evaluation during fermentation at $20^{\circ}C\;and\;5^{\circ}C$ (after keeping at $20^{\circ}C$ for 24 hours) were used. The results are as follows: As the fermentation period increases the pH of kimchi decreases. The pH of all samples rapidly decreases to 4.2. During fermentation, the acidity at 3 hours was higher than at 5, 8 and 12 hours. For in the sensory evaluation during fermentation, kimchi salted for 5 hours showed a higher score than those salted for 3, 8 and 12 hours. During the storage period, the pH of kimchi with salted oysters rapidly decreased. A sensory evaluation done during the storage period, showed that earlier on in the storage, kimchi with salted oysters was scored higher than kimchi with other Jeotkals. The leek-added kimchi was also highly scored.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1619-1625
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• 2012

The purpose of this study is to determine long-term storage conditions for winter kimchi. Kimchi was stored in a kimchi refrigerator for 6 months with or without fermentation. Four different temperature systems used were as follows: 5 days at $10^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F1), 1 day at $15^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F2), storage at $-1^{\circ}C$ (S1), or at $-2.5^{\circ}C$ (S2). Time periods required for F1, F2, S1, or S2 kimchi to reach pH 4.4 and acidity 0.6% were 2, 8, 12, and 22 weeks, respectively. Lactobacillus spp. growth on F1 and F2 kimchi was faster and greater than that on S1 and S2 kimchi, revealing a maximum concentration of 8~9 verses 6.8 log CFU/mL, respectively. However, Leuconostoc spp. were fully grown (8~9 log CFU/mL) on all four kimchi samples regardless of temperature, even at $-2.5^{\circ}C$, although the times required to reach maximum growth were different. Growth of Lactobacillus and Leuconostoc spp. both decreased after reaching maximum levels, except for F1 kimchi. Sensory evaluation results for 3 month storage showed that F1 kimchi was the best among kimchi samples in terms of appearance, acidic taste, carbonated taste, crispiness, and moldy smell. For 6 months of storage, F1 and S1 kimchi were the most highly evaluated among the kimchi samples. Sensory evaluation result for S1 kimchi stored at $-1^{\circ}C$ was comparable to that of F1 kimchi due to fully grown Leuconostoc spp. Acidities of F1 and S1 kimchi after 6 months of storage were 0.8 and 0.7%, respectively. Taken together, fermentation of kimchi at $10^{\circ}C$ for 5 days followed by storage at $-2.5^{\circ}C$ for 6 months was optimal for high quality kimchi. Sensory properties of winter kimchi were significantly influenced by the degree of fermentation.