• Food Science and Preservation
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• v.24 no.7
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• pp.1034-1042
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• 2017

The quality characteristics of Yakju and survival rate of yeast were investigated by modifying the drying method for the cold adapted yeast strain Saccharomyces cerevisiae Y297 (SCY297). Viability and fermentation characteristics of the freeze-dried, air blast-dried, and liquid SCY297 cultures were compared after storing them at $25^{\circ}C$. In addition, 5% skimmed milk, ${\alpha}$-lactose, or trehalose was added as a protective agent for examining the effects of drying methods. During the 15-week storage period, the liquid and freeze-dried SCY297 cultures containing a protective agent showed a survival rate of 80%. However, the air blast-dried SCY297 culture showed 80% survival rate only in the skimmed milk supplemented group. Compared to the untreated cells, the acidity and amino acidity of Yakju prepared using freeze-dried or air blast-dried cultures of SCY297 increased by 2 fold and 5.7 fold respectively, while the alcohol content decreased by 5.07%. Compared to the untreated cells, the pH and amino acidity of Yakju prepared using the liquid culture of SCY297 increased by 1.5 fold and 2.5 fold respectively. Although the alcohol content decreased by 2.9%, decrease rate was lower than that observed for the freeze-dried and air blast-dried yeast cultures. Therefore, the results of this study showed that using a liquid starter culture was more advantageous than using the conventional solid culture.

• 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.35 no.2
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• pp.246-253
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• 2003

Application of xylitol (Xyl) and grapefruit seed extract (GSE) to improve the quality and preservation of baechu kimchi was attempted. Xylitol and grapefruit seed extract at various combinatory concentrations were added into baechu kimchi and fermented for 25 days at $10^{\circ}C$. Assay was performed on sensory value, acidity, and bacterial growth. Addition of 0.1% GSE and 2% Xyl showed the highest score in the overall acceptability, sour taste, and texture. Score of intensity characteristics in smell and sour taste were the highest in the control and that of texture the highest in 0.1% GSE plus 2% Xyl treatment. The pH decreased, and titratable acidity, and growth of total viable cells and lactic acid bacteria were remarkably retarded in 0.1% GSE plus 2% Xyl group compared to the control. Results showed that application of 2% Xyl plus 0.1% GSE to the kimchi fermentation enhanced sensory value of the fermented product and extended the storage period by about twofold.

• Korean Journal of Microbiology
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• v.45 no.4
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• pp.391-396
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• 2009

This study was carried out to investigate the changes in yeast cell number, organic acid and total acid during the fermentation and distribution processes for enhancement of preservation of Makgeolli. Organic acids, including lactic acid, succinic acid, malic acid and citric acid, were increased with fermentation time, while oxalic acid, phosphoric acid and acetic acid were not detected, respectively. Production of organic acids leaded to pH reduction in Makgeolli. In case of Makgeolli kept at $4^{\circ}C$, there was no change in organic acids until 20 days. On the other hand, when observing the change in organic acid of Makgeolli kept at $25^{\circ}C$, concentration of lactic acid was decreased, while citric acid was not detected from the beginning of storage. However, acetic acid was detected from 10th day and rapidly increased at the 25th day. Therefore, it is suggested that the current expiration date (10 days in a cooler) could be extended.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.12
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• pp.1808-1815
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• 2016

In this study, quality characteristics of three different kinds of Gat Kimchi, added with Cheonnyuncho fruit (C-fruit) water extract, Cheonnyuncho cladodes (C-cladodes) water extract, and without Cheonnyuncho water extract (control group), were investigated during storage for 80 days at $5{\pm}1^{\circ}C$. In terms of mineral content of Gat Kimchi, C-fruit group showed higher calcium and zinc contents than the control group, whereas Cheonnyuncho groups showed higher iron content, and C-cladodes showed higher potassium content than the control group. The pH was mostly higher in Cheonnyuncho groups than in the control group until 40 days of storage, whereas the pH of the C-cladodes group significantly decreased after 60 days. On the other hand, titratable acidity showed the reverse tendency during storage. Hunter's color L, a, and b values all increased during the storage period. The hardness value was significantly higher in Cheonnyuncho groups than in the control group after 40 days of storage, and hardness value of the C-fruit group was significantly higher than those of the other groups after 80 days of storage. In terms of sensory evaluation, there was no significant difference between the control group and Cheonnyuncho group during fermentation. As a result, the study suggests that addition of C-fruit extracts increase nutrition and function of Gat Kimchi during storage.

• Journal of Dairy Science and Biotechnology
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• v.35 no.1
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• pp.25-31
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• 2017

This study was conducted to find means to reduce the foul smell emitted from chicken manure. Rice water was inoculated with Lactobacillus sakei and then examined to determine the bacterial survival rates during storage, and whether fermentation had occurred. Rice water was an excellent medium for the growth of L sakei, given that a viable cell count was maintained for 15 days during storage at $4^{\circ}C$ and decreased slightly thereafter. Furthermore, microorganisms in chicken manure were separated and 14 species were identified. The antibacterial activity of an L. sakei supernatant against the identified microorganisms was measured using the agar diffusion method. The growth of 11 out of 14 species was inhibited, and only Corynebacterium variabile, Enterococcus faecium, and Raoultella ornithinolytica survived. Rice water was fermented by inoculation with L. sakei and mixed with chicken manure, and the quantities of ammonia, ethyl mercaptan, and hydrogen sulfide were measured after 48 hours. Emissions of ammonia and ethyl mercaptan were reduced significantly.

• Food Science of Animal Resources
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• v.34 no.1
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• pp.40-48
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• 2014

In this study, the effects of two different commercial starter culture mixes and processing methodologies (traditional and heat process) on the lipolytic changes of fermented sausages manufactured with turkey meat were evaluated during processing stages and storage. Free fatty acid (FFA) value increased with fermentation and during storage over 120 d in all fermented sausage groups produced with both processing methodologies (p<0.05). After drying stage, free fatty acid values of traditional style and heat processed fermented sausages were between 10.54-13.01% and 6.56-8.49%, respectively. Thiobarbituric acid (TBA) values of traditionally processed fermented sausages were between $0.220-0.450mg{\cdot}kg^{-1}$, and TBA values of heat processed fermented sausages were in a range of $0.405-0.795mg{\cdot}kg^{-1}$. Oleic and linoleic acids were predominant fatty acids in all fermented sausages. It was seen that fermented sausage groups produced with starter culture had lower TBA and FFA values in comparison with the control groups, and heat application inhibited the lipase enzyme activity and had an improving effect on lipid oxidation. As a result of these effects, heat processed fermented sausages had lower FFA and higher TBA values than the traditionally processed groups.

• Microbiology and Biotechnology Letters
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• v.9 no.1
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• pp.7-19
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• 1981

The production of gluconic acid from glucose by the resting cell system of Aspergillus niger was studied. It was found that the conversion products from glucose by the resting cell system were markedly influenced by the pH, temperature, substrate concentration, aeration, metal ions, cultivation time and storage conditions of the resting cells. Conversion products were identified as gluconic acid by the thin layer chromatography and infrared spectrophotometry. These conversions were greatly stimulated by addition of $Mg^{++}$, and S $n^{++}$, but showed inhibitory effects by C $u^{++}$, H $g^{++}$, C $d^{++}$, A $g^{+}$ and cyanide. For the optimum cell storage, it was effective to be kept at -$25^{\circ}C$ in 0.05M phosphate buffer solution of pH 7.0. The gluconic acid production by the resting cell system was more effective than those of the fermentation with respect to cultivation time, yield, recovery and re-use of the cell.l.l.l.l.l.l.

• The Korean Journal of Community Living Science
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• v.22 no.1
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• pp.77-94
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• 2011

It is not clear to assume the history of dyeing by persimmon juice without an early knowledge of an accurate record. However, the beginning of persimmon dyeing in Korea is estimated to be around the $13^th$-$14^th$ century, even though there are no supporting records. On the other hand, there are definite records of persimmon dyeing in Japan from around the 17th century. Persimmon juice was originally used for fishing tools in both Korea and Japan, but upon entering the Modern Era it eventually transfigured into a dye for fabric. In Korea, persimmon-dyed fabrics were used for traditional clothing until it also became a popular choice for modern clothes in the 1990s. In Japan, persimmon juice was originally used for varnishing surfaces of household items, but it recently became a material for arts, crafts, and even apparels. The main difference between persimmon dyeing of the two countries is the presence and absence of the fermentation process. In Korea, persimmons are picked and water is immediately added to its juice to produce the dye. In contrast, Japan produces a fermented persimmon dye. As a result, in Korea the dye can not be preserved for long periods, whilst in Japan it is matured in the storage for 2-3 years. Today's pursuit of eco-friendliness and wellness has prompted an inclination towards natural material clothes. Therefore, it is necessary for both countries to push scientific research into improving the storage methods and colorfastness of persimmon-dyed products for the increase of use consumption in other areas of persimmon and arrowroot dyed fabrics, and the development of environment friendly materials.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.322-327
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• 2004

This study was carried out to evaluate the effect of flour's protein contents on the quality of Danish pastries made with frozen doughs. Danish pastries for frozen dough were made by straight dough method. Frozen doughs were stored for 12 weeks at -20$^{\circ}C$ and baked after thawing and fermentation a month. The volume, the moisture content, the texture and the quality evaluation of Danish pastries were investigated. The volume of Danish pastry decreased with the increase of frozen storage time. Danish pastry made by flour of 13.2% protein content showed larger volume than that made by flour of 9.2% protein content. The moisture content of Danish pastry revealed that there were no significant decrease with the increase of frozen storage time. In terms of hardness, Danish pastry made by flour of 9.2% protein content accomplished the best texture in the resulting pastry. On the quality evaluation, Danish pastry made by flour of 13.2% protein content had the highest score.