• Journal of the Korean Society of Food Culture
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• v.20 no.4
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• pp.468-475
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• 2005

To determine the effect of different fermentation level on the quality of Nabak Kimchi during storage, this study was carried by analysing the result of physico-chemical properties, microbiological characteristics and sensory evaluation of Nabak Kimchi stored up to 24 days. For the physico-chemical properties, pH, total acidity, reducing sugar, carbon dioxide contents, color values were investigated while for the microbiological characteristics, total microbial counts and lactic acid bacteria were studied. Nabak Kimchi products were fermented at six different level of temperature and time and stored in Kimchi refrigerator at $4^{\circ}C$ for 24 days. As the storage period increased, the pH values of LF15, SF25 and LF25 decreased rapidly after initial fermentation and the pH values of SF4, LF4 and SF15 increased slightly in the beginning and then decreased. total acidity increased as storage period proceeded. the amount of reducing sugar was 4.92mg/ml before fermentation and increased significantly and reached its maximum values then decreased. lightness and redness of Nabak Kimchi decreased as storage period became longer, but yellow of Nabak Kimchi increased during storage. Total microbial counts of SF25 and LF25 reached to the highest at the 6th day and total microbial counts of LF15 reached to the highest at the 12th day and then significantly decreased. However, total microbial counts of SF4, LF4 and SF15 continuously increased up to the 24th day. The number of lactic acid bacteria was similar to the phase of the change of total microbial counts.

• Journal of Dairy Science and Biotechnology
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• v.30 no.1
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• pp.23-30
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• 2012

This study was carried out to investigate the quality characteristics of yoghurt with varying contents of Sanmeoru (Vitis amurensis Ruprecht) wine (SW). Yoghurts were fermented with 2 kinds of lactic acid bacteria (Streptococcus thermophilus and Lactobacillus bulgaricus; Yo-$MIX^{TM5}505$, Danisco, Denmark). The changes in quality characteristics were investigated during fermentation and storage, and anthocyanin composition was analyzed after fermentation. The pH decreased in all treatments, while titratable acidity and viscosity gradually increased during fermentation. The viscosity of the yoghurt with 5.0% cultured SW added was higher than in other groups. The viable counts of lactic acid bacteria gradually increased during fermentation. The sample of the 5.0% cultured SW-yoghurt was higher than that of the other groups. The pH slowly decreased during the storage period; this was lower in the control yoghurt than in the yoghurts containing SW, and the changes of titratable acidity in the samples containing 5.0% and 30.0% cultured SW were lower than that in the yoghurt containing 1.0% cultured SW and in the control. The change in viscosity and number of viable cells during storage was higher in the yoghurts containing SW than in the control group. The levels of anthocyanin increased with the SW content in the yoghurt. Sensory scores for taste of the yoghurt with 1.0% added SW was significantly higher than for the other groups. Yoghurt with added SW kept at $4^{\circ}C$ for 12 days retained its quality characteristics fairly well.

• Journal of Food Hygiene and Safety
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• v.36 no.3
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• pp.271-279
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• 2021

Sweet pumpkin is rich in minerals such as calcium, phosphorus and fiber, and also contains a large amount of β-carotene, which has antioxidant effects. In this study, Makgeolli containing steaming sweet pumpkin (SP) was manufactured to enhance the antioxidant activity. To prepare the Makgeolli, SP was added in amounts of 5, 10, 20, and 30% (w/w), and the chemical (pH, total acidity, alcohol), microbiological (lactic acid bacteria, yeast) properties, and antioxidant activities (DPPH, ABTS) were examined during fermentation and storage for 9 days. The pH of SP Makgeolli was 4.00-4.23 at day 1 of fermentation, and then the pH gradually decreased as fermentation progressed, showing the lowest results at day 9 (3.28-3.52). At day 1, the total acidity was significantly increased (P<0.05) as the amount of SP (0-30%; 0.09-0.55%) and the total acidity in SP Makgeolli (1.01-1.20) was also rapidly increased by 5 days of fermentation. Alcohol content was significantly increased (P<0.05) as the amount of SP (0-30%; 4.59-5.77%) increased at day 9. The counts of lactic acid bacteria and yeast in SP Makgeolli were 8.0-8.1 and 7.9-7.8.0 CFU/mL, respectively, which was higher than SP 0% at day 9. DPPH and ABTS radical scavenging activities were significantly increased (P<0.05) as the amount of SP (0-30%; 48.29-78.97% for DPPH, 62.12-86.68% for ABTS) increased at day 9. This study suggests that Makgeolli added with SP could be potentially and commercially developed due to its superior microbiological and chemical properties, including high antioxidant activities.

• Food Science and Preservation
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• v.17 no.6
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• pp.793-799
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• 2010

Kimchi was fermented in permeability-controlled polyethylene containers, in glazed onggi (Korean ethnic earthenware) or glass bottles at $5^{\circ}C$ for 8 weeks. During 4 weeks of storage, kimchi fermented in the permeability-controlled container showed a stable fermentation pattern, in terms of changes in pH and acidity, compared with kimchi fermented in the other containers. With respect to changes in bacterial counts, kimchi fermented in polyethylene containers showed vigorous multiplication of lactic acid bacteria, especially Lactobacillus sp., but slow growth of total aerobic bacteria. The springiness of kimchi fermented in the polyethylene containers was optimal (about 10% more than that of glass bottle-fermented kimchi), and the overall acceptability and hardness of container-fermented kimchi were excellent upon sensory evaluation. The DPPH radical-scavenging activity of kimchi fermented in polyethylene containers was also greater (91%) than that of kimchi fermented in glazed onggi (73%) or glass bottles (63%). The $O_2$ and $CO_2$ permeabilities of the polyethylene containers were higher (458 and $357\;mmol\;h^{-1}\;m^{-2}\;atm^{-1}$, respectively) than were those of the other containers; the permeability ratio was 0.8. Glass bottles showed no permeance. The results indicate that permeability-controlled polyethylene containers may be used for kimchi fermentation.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1404-1408
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• 1998

These studies were carried out to investigate the effect of mixed medicinal herbs, such as Curcuma longa and Lithospermum erythrorhozon (CL), Lithospermum erythrorhozon and Sophrora flavescens AITON (LS), Sophrora flavescens AITON and Glycyrrhiza uralensis (SG), and Glycyrrhiza uralensis and Schizandra chinensis (GS) on shelf-life of kimchi. The pH of kimchi containg 1% of medicinal herb extracts such as CL, LS, SG and GS was higher than that of control during fermentation for 25 days at $10^{\circ}C$ Titratable acidity, viable cells count of total bacteria and lactic acid bacteria in the kimchi were changed more slowly than in control. Shelf-life of kimchi was extended by addition of 1% mixed medicinal extracts such as CL, LS, SG and GS (1:1), respectively. The sensory quality (taste, flavor, crispness and overall acceptability) of CL, LS, SG and GS added kimchi was similar to that of control at 10 days of fermentation. But the sourness of LS, SG and GS (1%) added kimchi was more slowly developed than control after 15 days of fermentation, respectively. The effect of LS, SG and GS mixture on shelf-life in kimchi was significant. But the medicinal herb extracts added kimchi decreased its sensory quality with increasing concentration of the extracts.

• Korean Journal of Food Science and Technology
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• v.50 no.4
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• pp.400-406
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• 2018

Takju and yakju are traditional Korean alcoholic beverages that are prepared by fermentation of glutinous rice with nuruk, a cereal starter containing various bacteria, fungi, and yeast. In this study, physicochemical and microbial properties of a total of 12 commercial takju and yakju samples were analyzed; their pH, sweetness, and alcohol content were varied, depending on the type of alcohol, from pH 3.64-4.8, $5.1-24.8^{\circ}Bx$, and 4.6-18.5%, respectively. Microbial communities were analyzed with 16S rRNA amplicon sequencing using MiSeq system. At the phylum level, Firmicutes (86.2%) was the most dominant, followed by Proteobacteria (8.08%), Actinobacteria (2.56%), and Cyanobacteria (3.13%). Lactic acid bacteria, including Lactobacillus, Lactococcus, Leuconostoc, and Weissella were also frequently detected. Among eukaryotes, Saccharomyces cerevisiae was the most dominant in these samples.

• Korean Journal of Microbiology
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• v.15 no.3
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• pp.103-112
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• 1977

Several strains of spore-forming lacticacid bacteria were isolated from natural sources such as soils, cereals, and foods. The general morphological and physiological characteristics of the strain 6-4 were investigated nad compared with some other industrial strains. The effects of fructose-1,6-diphoshpate (FDP), adenosine triphosphate (ATP), and pH on the lactate dehydrogenase(LDH) activity of the strain were studied, and the changes in LDH activity and spore formation under various cultural conditions were researched. The results were as follows. 1. This strain was identified to Bacillus coagulans Hammer and distributed widely in natural sources. 2. The strain strongly converted various fermentation substrates in to L(+)-lacticacid in anaerobic conditioins, and many spores that were of great advantages to the industrial application were formed easily in the aerobic condition. 3. The LDH activity of this strain was activated by FDP and inhibited by ATP. The optimal pH for the enzyme activity was 6.0-6.5. 4. In the anaerobic culture condifion, the large amount of glucose added in the medium increased the LDH activity, but the cells were not committed to sporulate. 5. When none or a very small amount of glucose (less than 0.5%) was added to culture medium in the aerobic condition, the LDH activity was decreased and many spore were produced with final pH higher than 8.5. 6. The additioin of large amount of glucose (more than 2.0%) in aerobic culture increased the LDH activity and inhibited strongly the spore formation with final pH lower than 6.0.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.2
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• pp.216-221
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• 2007

Microbiological, chemical and sensorial quality changes of kimchi, which was manufactured with sanitized materials by ozone and gamma irradiation, were investigated during storage. The number of total aerobic bacteria in control was increased rapidly by storage and decreased after 10 days of storage. However, the kimchi which was manufactured with materials treated with ozone or gamma irradiation showed a lower rate of increase. The number of lactic acid bacteria was lower in control than in treatments. Gamma irradiation of 3 or 5 kGy showed the lowest change of microbial population in kimchi during storage. pH, acidity and sensory quality were also rapidly changed in control whereas those of ozone or irradiation treated sample was slower. Therefore, cold pasteurization of materials before kimchi manufacturing provide a slower fermentation, resulting into the extension of storage quality for kimchi.

• Journal of the Korean Society of Food Culture
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• v.30 no.6
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• pp.757-765
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• 2015

The objective of this study was to determine the quality characteristics of fermenting mash and pasteurized ginseng Makgeolli added with different concentrations of ginseng powder. Total aerobic bacteria and lactic acid bacteria counts of mash added with 0, 1, 2, and 4% ginseng powder during 4 days of fermentation significantly increased, whereas yeast count decreased. Viable cell count remarkably decreased after pasteurization. Pasteurized 4% ginseng Makgeolli (4.30) showed a higher pH than 0, 1, and 2 % ginseng Makgeolli (4.09, 4.08, and 4.06, respectively) after 15 days of aging. After aging, amylase activity of pasteurized Makgeolli decreased, and 0% and 1% ginseng Makgeolli (22.35, $21.55^{\circ}Brix$) showed higher Brix content than 4% ginseng Makgeolli ($20.15^{\circ}Brix$). Before aging, alcohol contents of 0, 1, 2, and 4% pasteurized ginseng Makgeolli were 5.80, 5.50, 5.20, and 5.10%, respectively. After 15 days of aging, 0% ginseng Makgeolli (7.00) showed higher alcohol content than 1, 2, and 4% ginseng Makgeolli (5.90, 5.80, and 5.60%, respectively). The results of the sensory evaluation show that 2% ginseng Makgeolli after 3 days of aging at $4^{\circ}C$ had the highest scores for taste (5.19), flavor (5.04), and overall acceptability (5.22) among the samples.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2019.04a
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• pp.110-110
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• 2019

Beet (Beta vulgaris) is a crop similar to sugar beet, chard and leaf beets, and its origin is the Mediterranean coast of southern Europe and Central Asia. Among the components contained in beet, betalain, the main component of the root, has been reported to prevent lipid peroxidation induced by active oxygen and free radicals due to its high radical scavenging ability. Among these, the betalain, betanin (Betanidin 5-O-${\beta}$-glucoside) contains both phenolic and cyclic amine groups, all of which are highly electron-donating and act as antioxidants and has tyrosinase inhibitory activity. Betanin accounts for about 75-95% of the total pigment found in the beet. EM stands for effective microorganisms and is a collection of beneficial microorganisms. EM includes yeast, lactic acid bacteria, mycelia, photosynthetic bacteria, actinomycetes, etc. Human patch test according to CTFA guidelines was observed to be a safe source of no stimulation when 5% (v/v) of the EM fermentation liquid was applied to the human body. In addition, beneficial microorganisms are synergistic in the process of co-existence and cultivation and it has the effect of increasing antioxidant capacity and inhibiting corruption. This study confirms the difference in tyrosinase inhibitory activity and betanin content of beetroot extracts and EM fermented beetroot extracts. Hence, these results confirm that EM fermented beetroot extracts are highly beneficial for the human body.