• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.3
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• pp.127-131
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• 2019

The effects of lactic acid bacteria (LAB) mixtures on low moisture Italian ryegrass (IRG) silage fermentation was evaluated in field conditions. The experiment was categorized into two groups: Un-inoculated (Control) and Inoculated with LAB mixture for four storage periods (45, 90, 180, and 365 days, respectively). Silage inoculated with the LAB mixture had the lowest pH with highest lactic acid production than the control from beginning at 45-365 days at all moistures. Higher LAB counts were observed in inoculated silages than the control silages at whole experimental periods. It is a key reason for the rapid acidification and higher lactic acid production in silages during the storage periods. Overall results suggest that an adding of LAB mixture had positive effects on the increasing aerobic stability of silage and preserved its quality for an extended duration.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.541-546
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• 1992

In order to develop low salt fermented hen clam sauce with high stability, the effects of citric acid pretreatment and fermentation temperature were examined. The VBN contents of surf clam sauce treated with citric acid (SCA) were lower than those of control and the same sauces added alcohol at two temperature conditions ($5^{\circ}C$ and room temperature) during fermentation. The maximum $NH_2-N$ contents of control and SCA during fermentation at $5^{\circ}C$ were 501.3 and $618.4{\sim}691.6\;mg/100g$, respectively, and the pH of those showed $5.61{\sim}6.24$ and $2.43{\sim}3.21$. The total creatine contents of control and SCA, respectively, were $36.8{\sim}27.6\;mg/100g$ ranges. As the time of treatment with citric acid was longer, the degradation of ATP, ADP and AMP in the SCA was faster. In the control, the Ala content was $19.6{\sim}23.02%$ and was highest level among all free amino acids. As fermenting term was longer, among the free amino acids, Ala and Gly were large amounts in control and SCA, respectively, and Gly was slowly increased in SCA during fermentation. As the results of organoleptic test, the tastes of SCA showed good score than control.

• Food Science and Preservation
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• v.17 no.3
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• pp.320-327
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• 2010

The physicochemical and sensory properties of Baik-Kimchi supplemented with Lotus root juice were periodically examined during fermentation at $5^{\circ}C$ over 4 weeks. The pH decreased and acidity gradually increased during fermentation. Turbidity also increased as the level of added Lotus root juice increased, with a gradual rise being evident over 2 weeks with a subsequent decrease to the 4-weekpoint of fermentation. The L- and a-values decreased as the amount of added Lotus root juice increased, whereas the b value increased. The reducing sugar content increased when Baik-Kimchi was supplemented with 3% or 6% (both w/v) Lotus root juice, but decreased when Baik-Kimchi was supplemented with 9% or 12% (both w/v) root juice. Reducing sugar content decreased as fermentation continued. The vitamin C content was higher in supplemented samples, than in the control during fermentation. The hardness of Baik-Kimchi supplemented with Lotus root juice decreased with increasing fermentation time. By sensory evaluation, addition of 6%(w/v) root juice yielded a product superior in color, smell, crispness, and overall acceptability compared with control. In conclusion, optimal Baik-Kimchi fermentation should include addition of 6% (w/v) Lotus root juice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1587-1594
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• 2009

This study investigated the physico-chemical and sensory quality of Doenjang added with red pepper (Capsicum annuum L.) seed. The initial moisture content and salt content of Doenjang were 52.03-53.79% and 13.28-14.05%, respectively. The moisture and salt contents of Doenjang slightly decreased and increased, respectively, as fermentation periods increased. According to increasing fermentation periods, pH of Doenjang showed a little decreasing value although there were no difference between samples with various red pepper seed contents. On the other hand, titratable acidity of Doenjang increased as fermentation periods increased. Also, Doenjang added with red pepper seed had higher titratable acidity value than control Doenjang without red pepper seed. In the color of Doenjang, ‘L’ of lightness, ‘b’ of yellowness, and ‘a’ of redness were decreased as fermentation periods increased. Also, generally, increase of red pepper seed concentration resulted in higher values of redness (a), yellowness (b) and lightness (L) of Doenjang. Also, amino-type nitrogen content, which was 497-623 mg% in initial fermentation period samples, increased to 1,000 mg% for control and to 756~896 for red pepper added at the fermentation 120 days. In the total microbes, total cell count in the Doenjang samples was in the range of $10^7{\sim}10^8$ CFU/g regardless of fermentation periods. In contrast, yeast and mold number of Doenjang samples showed the range of $10^5$ CFU/g at the initial fermentation periods and decreased thereafter. In the sensory evaluation of Doenjang, unique Doenjang flavor increased regardless added red pepper seed as fermentation periods increased.

• Microbiology and Biotechnology Letters
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• v.43 no.4
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• pp.350-356
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• 2015

There have been several studies on role of hormesis with light stimulation, however, the influence of light on fermentation is still poorly understood. In this study the relationship between LED (light emitting diode) hormesis and ethanol fermentation for Muscat bailey A wine was investigated. Two LEDs, one blue ($453{\pm}4nm$) and one green ($522{\pm}3nm$), were used. Both LED groups showed an inhibited production of lactic acid. The blue LED stimulated the growth of the yeast in early stage of the fermentation. Polyphenolic compounds and their antioxidant abilities were significantly increased by the green LED. These results demonstrate that LED irradiation must bring about hormesis and affect the growth rate of yeast in the early stage of the fermentation, and the contents of phytochemicals during fermentation. These findings indicate the possible application of LED hormesis for the wine fermentation. Further studies are needed to understand how LED irradiation induces hormesis effects during the fermentation process.

• Food Science and Preservation
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• v.18 no.5
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• pp.706-713
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• 2011

This study was conducted to investigate the chemical characteristics of Gochujang with different amounts of sweet persimmon powder added during fermentation at $20^{\circ}C$ for 90 days, in an effort to improve its taste and organoleptic quality. The moisture content was shown to be inclined to increase in all the treatments throughout the fermentation. There was no significant difference between the paste with sweet persimmon powder and the control. The pH showed a tendency to decrease with increased fermentation time in all the samples during fermentation, keeping a pH range of 4.64-4.67 after 60 days of fermentation. On the contrary, the titratable acidity increased during fermentation, showing a level of 0.147-0.156 mg% in the paste with sweet persimmon powder on the 90th day of fermentation. The sugar content was shown to be $33.67-39.67^{\circ}Brix$ in the early stage of fermentation, revealing a tendency to in crease with an increase in the amount of sweet persimmon powder added. The amino-type nitrogen content was at the 241.27-245.47 mg% level in the early stage of fermentation, and appeared to be significantly high (p<0.05) in the treatments with 3 and 4% sweet persimmon powder added, respectively, after 60 days of fermentation. The content was within the range of 357.47-371.53 mg% on the 90 th day of fermentation in the final stage, showing an increase trend throughout the fermentation. The alcohol content gradually increased with an increase in fermentation time, showing a range of 0.94-0.10% on the 90th day of the final stage of fermentation. Moreover, the content was highest (0.96-0.108%) on the 70th day of fermentation, demonstrating a trend to slightly decline in all the treatments thereafter.

• Food Science and Preservation
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• v.8 no.2
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• pp.151-156
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• 2001

Acetic acid solution containing calcium (AC) was added to kimchi seasonings by 10% and 205, and heat treatment at 70$\^{C}$ for 15 min was also tried, respectively. Kimchi with treated seasonings was investigated for the quality during fermentation at 10$\^{C}$. Heat treatment with 20% AC showed a retarded decrease pH than others on 10 days, but there was no great difference after 14 days. Higher titratable acidity was revealed in kimchi with AC during the fermentation. Total microbial lead and lactic acid bacterial count were generally lower in kimchi with AC. Reducing sugar content was maximum for all samples on 5 days, and then decreased thereafter. Redness of control kimchi was steadily increased during fermentation, but was lower than those of other treatments.

• Journal of Sensor Science and Technology
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• v.18 no.1
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• pp.72-76
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• 2009

The sensing system was designed and fabricated to investigate the ferment environment of soybeans. $NH_3$ gas was saturated after about 7 h and $CO_2$ gas was reached the peak after about 8 h in the inoculation of Bacillus subtilis. However, times that $CO_2$ gas and $NH_3$ gas were reached maximum value without Bacillus subtilis were about 15 h and 18 h, respectively. The sample that inoculated Bacillus subtils had deeper taste than one without it. We found that the peak time of $CO_2$ gas means the starting time of fermentation. If we control the operating time after the start of fermentation, it is expected to make a suitable Chungkukjang to individual preference.

• Microbiology and Biotechnology Letters
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• v.17 no.6
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• pp.619-623
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• 1989

The effects of temperature on yeast growth and ethanol production were investigated in batch cultures. The maximum specific growth rate of yeast was obtained at 36$^{\circ}C$ and the maximum specific production rate of ethanol was obtained at 33$^{\circ}C$. A mathematical model was employed to describe the temperature effects in ethanol fermentation and the parameters in the model were expressed as a function of temperature. Optimum temperature control strategy, from the simulation result, consists of starting the fermentation at high temperature and lowering the temperature as the fermentation proceeds.

• Preventive Nutrition and Food Science
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• v.14 no.3
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• pp.265-268
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• 2009

Three-hundred bacterial isolates from a natural cheese were screened for the production of bifidobacterial growth factor by whey fermentation. Based on this screen, two whey samples fermented by strains designated as CJNU 0421 and CJNU 0588 were found to effectively stimulate the growth of a bifidobacterial strain, Bifidobacterium longum FI10564, by 1.6$\sim$1.7 fold compared to a control, in which non-fermented whey medium was added. The two isolates were identified to be Lactobacillus casei (99% identity) by 16S rRNA gene sequencing and named Lactobacillus casei CJNU 0421 and CJNU 0588, respectively. The whey sample fermented by CJNU 0588 did not enhance the growth of other bacteria such as Escherichia coli and Listeria monocytogenes, suggesting that the whey fermentation metabolites from the isolate could be used for the selective stimulation of bifidobacteria.