• Food Science and Biotechnology
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• v.17 no.5
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• pp.895-898
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• 2008

The mobility of water in set yogurt during fermentation was studied using nuclear magnetic resonance (NMR) relaxometry. The spin-spin relaxation was analyzed using a 2-fraction model, resulting in 2 spin-spin relaxation time constants $T_{21}$ and $T_{22}$. Both $T_{21}$ and $T_{22}$ exhibited rapid changes between 2 and 4 hr of fermentation, coinciding with the drop in pH and the rise in lactic acid bacteria count. The spin-lattice relaxation time $T_1$ increased over the fermentation period. Both $T_1$ and $T_2$ showed an increase in the mobility of water upon gel formation during fermentation. Water redistribution within the gel matrix due to casein aggregation and structure forming may be responsible for the changes in mobility.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.142-149
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• 2011

The purpose of this study was to elucidate the physicochemical and microbiological properties of Korean traditional rice wine, Makgeolli, supplemented with black garlic extract during fermentation. Black garlic extract was diluted with distilled water to produce 0.5% and 1.0% black garlic solutions. Those solutions were then used to make rice solutions which included 2 kg rice, 40 g Nuruk (a fermentation starter), and 14 g yeast. After being mixed, the rice solutions were fermented for 7 days in a water bath at $28^{\circ}C$. The alcohol contents of the control, 0.5% and 1.0% black garlic Makgeolli were 16.9, 16.0, and 16.2%, respectively. Total acidity, total soluble solids, and color increased throughout the fermentation process. There was an increase of microorganisms throughout the fermentation period in all the samples. Glucose was the highest free sugar, and succinic acid was the highest organic acid detected in all the samples. Thirty nine volatile compounds were detected in black garlic Makgeolli.

• The Korean Journal of Food And Nutrition
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• v.11 no.5
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• pp.570-575
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• 1998

This paper presents an investigation of chemical and sensory properties of Kimchi with red-ripe persimmon. Kimchi with different levels(0, 5, 10, 15%) of real-ripe persimmon was fermented at 4$^{\circ}C$ for 20days. During the fermentation, pH decreased in all Kimchi samples and pH of Kimchi with red-ripe persimmon was a little lower than that of Kimchi without red-ripe persimmon. Acidity increaased continuously and saltiness was maintained at 1.2∼2.2% levels during fermentation. The reducing sugar of Kimchi with red-ripe persimmon was relatively higher than that of the other sample without red-ripe persimmon. Total vitamin C(Vit. C) in Kimchi added red-ripe persimmon increased in the early stage of fermentation and reduced gradually after 4days of fermentation. In the sensory evolution, Kimchi with 10% red-ripe persimmon recorded high scores in taste, flavor, texture and overall acceptability during all fermentation period.

• The Korean Journal of Food And Nutrition
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• v.16 no.3
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• pp.218-223
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• 2003

This study is proceeded on the development of standard method for making soybean paste by Korean traditional method. Fermentation condition of Meju was 1) Pre-fermentation : 30 days in about 20$^{\circ}C$ room, 2) Main fermentation : 5 days in 30$^{\circ}C$ or upper temperature, 3) Post fermentation and drying : 30 days in well sunlightened room in January. Meju was soaked in 18% salt solution(Meju 7kg/salt solution 20L) for 35～40 days (from late February to early April) and after soaking Meju was filtered as unsoluble solute and crushed and put into traditional Korean receptacle(named 'Dok'). Crushed Meju was stored from early April to mid September and Meju was changed into soybean paste(Doen-jang). During fermentation amino acid nitrogen in Doen-jang was slightly increased in early period and decreased lately. It has been proved that by panel test soybean paste made by the method suggested in this study was more excellent than commercially fermented soybean paste. This study has presented the possibility of commercial production of soybean paste made by traditional method.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.3
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• pp.363-368
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• 2018

Objective: The objective of the study was to determine the effect of fermented spent coffee ground (FSCG) on nutrient digestibility and nitrogen utilization in sheep. Methods: Fermentation of spent coffee ground (SCG) was conducted using Lactobacillus plantrum. Fermentation was performed at moisture content of 70% and temperature of $39^{\circ}C$ with anaerobic air tension for 48 h. Four adult rams (initial body weight = $56.8{\pm}0.4kg$) were housed in a respiration-metabolism chamber and the treatments were: i) control (Basal diet; 0% SCG or FSCG), ii) 10% level of SCG, iii) 10% level of FSCG, and iv) 20% level of FSCG in $4{\times}4$ Latin square design. Each dietary experiment period lasted for 18-d with a 14-d of adaptation period and a 4-d of sample collection period. Results: In SCG fermentation experimental result, acid detergent insoluble nitrogen (ADIN) concentration of FSCG (64.5% of total N) was lower than that of non-fermented SCG (78.8% of total N). Digestibility of dry matter and organic matter was similar among treatment groups. Although crude protein (CP) digestibility of the control was greater than FSCG groups (p<0.05), the 10% FSCG group showed greater CP digestibility and nitrogen retention than non-fermented 10% SCG group (p<0.05). Body weight gain and average daily gain were linearly decreased with increasing FSCG feeding level (p<0.05). When the feeding level of FSCG was increased, water intake was linearly increased (p<0.05). With an increasing FSCG level, dry matter intake did not differ among groups, although the gain to feed ratio tended to decrease with increasing level of FSCG (p<0.10). Conclusion: Microbial fermentation of SCG can improve protein digestibility, thereby increasing CP digestibility and nitrogen utilization in sheep. Fermentation using microorganisms in feed ingredients with low digestibility could have a positive effect on improving the quality of raw feed.

• Journal of Food Hygiene and Safety
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• v.12 no.4
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• pp.333-339
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• 1997

The effects of kind of vegetables and of the kind and amounts of fermented fish sauce on the formation of nitrosamine (NA) during kimchi fermentation were investigated. Kimchies made of Chinese cabbage, cucumber, and radish with fermented shrimp, anchovy and liquid sauces were fermented at 4$^{\circ}C$ for 6 weeks and the changes in the content of nitrate, nitrite, trimethylamine (TMA), dimethylamine (DMA) and NA were studied. Nitrate content in kimchies made of Chinese cabbage, cucumber, and radish increased at the initial period of fermentation, but it decreased at the later period. Nitrite was not detected at the later period of kimchi fermentation. Overall, there have not been great changes in the contents of nitrite and nitrate. However, there have been considrable changes in the contents of TMA and DMA as fermentation progressed. Only nitrosodimethylamine (NDMA) at the level of 0.5~10.3 $\mu\textrm{g}$/kg was formed in three kinds of kimchies. More NDMA was formed in radish and cucumber kimchies than in Chinese cabbage kimchi. The pH was lowered faster in radish and cucumber kimchies than in Chinese cabbage kimchi. More NDMA was formed in Chinese cabbage kimchi made with fermented shrimp sauce than those with anchovy or liquid sauces. Shrimp sauce contained higher amount of DAM than anchovy and liquid sauces. The contents of NDMA tended to increase as the amount of shrimp sauce increased. The kind and amount of fermented fish sauce used for kimchi preparation may be an important factor affecting the formation of NDMA.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.265-269
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• 2003

Gamma irradiation treatment was performed at the early and mid-fermentation stages of Kimchi preparation. Changes in fermentative microorganisms and lactate dehydrogenase activity during the fermentation periods were investigated to determine proper irradiation point for extending the shelf life of Kimchi. Initial levels of acid producing bacteria and yeast in Kimchi were 10$^4$ CFU g$^{-1}$ and 10$^1$ CFU g$^{-1}$ , and reached up to 10$^{9}$ CFU g$^{-1}$ after 15 days and 10$^{7}$ CFU g$^{-1}$ after fermentation for 30 days at 1$0^{\circ}C$, respectively. The radiation resistance of acid producing bacteria in the earlier stage (D$_{10}$ value was 0.87 kGy) was higher than at the midfermentation stage (after 10 days at 1$0^{\circ}C$, D$_{10}$ value was 0.69 kGy). Microbial growth and lactate dehydrogenase activity were inhibited significantly by gamma irradiation at the early fermentation stage of Kimchi and acidification was effectively delayed during the subsequent storage period. Although the growth of fermentative microorganisms was inhibited by gamma irradiation at the mid-fermentation stage of Kimchi, lactate dehydrogenase activity was maintained and acidification continued during the storage period.

• Culinary science and hospitality research
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• v.24 no.1
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• pp.39-49
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• 2018

In this study, the traditional takju was manufactured using the finger root, which was recognized as a health functional ingredient, and analyzed the physicochemical and sensory quality characteristics according to the period of fermentation. The pH was significantly low(p<0.05) in all samples until the second day of fermentation, and the pH tended to increase again from the third day of fermentation. The pH value was decreased as the amount of finger root was decreased(p<0.05). The acidity of takju was significantly lower at 0.17~0.21 immediately after fermentation(p<0.05). The acidity of FR0 showed significantly the highest value(p<0.05). The sugar content of takju was significantly increased in all the samples until the 2nd day of fermentation(p<0.05). On the 7th day, it showed the lowest value at $11.01{\sim}12.63^{\circ}Brix$. The sugar content of FR0 was significantly lowest value(p<0.05). The alcohol content of takju was significantly increased as the fermentation proceeded, and the highest value was 11.90~13.50% at 7 days(p<0.05). The alcohol content of RF0 was significantly higher than other samples(p<0.05). As a result of organic acid analysis of finger root takju fermented for 7 days, citric acid(3.35%) showed the highest content of FR3(p<0.05). The content of fructose increased with increasing finger root amount (p<0.05). As a result of sensory evaluation of finger root takju, FR1 and FR2 samples tended to be lower in score than FR0, and FR3 showed the highest score. The overall acceptance value of FR0 was 7.5 and FR3 was 7.57.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.751-759
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• 2018

This study was conducted to investigate quality characteristics of red bean gochujang prepared with different ratios of meju for eight weeks. We determined quality characteristics such as pH, moisture content, total microbial flora counts, amino-type nitrogen content, total polypenol content, and antioxidant activity. The pH decreased by fermentation period, whereas total acidity was 0.36~0.39% in the early stage of fermentation, 0.63~1.16% at four weeks of fermentation, and decreased to 0.43~0.65% after the eighth week of fermentation. Moisture content of the control (no red bean, no rice) decreased 62.13% to 50.93%, but in case of the treatment, it slightly decreased. Total cell counts revealed similar tendency at the beginning of fermentation, and at eight weeks of fermentation. In case of lactic acid bacteria, all samples except RB-1.5 (gochujang added meju made of mixing ratio of rice:soybean:red bean (1:2:1.5) slightly increased. Amino nitrogen and total polyphenol of all samples increased in the fermentation period, especially RB-1.5 sample had the highest levels than other samples. By increasing the amount of red bean, DPPH radical scavenging activities increased. In taste sensing analysis, all treat samples except RB-1.5 revealed lower sourness than the control. Also, in case of bitterness, all samples revealed low content than the control. So, by adding red bean, it can enhance taste and function of gochujang.

• Food Science of Animal Resources
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• v.33 no.6
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• pp.744-751
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• 2013

The objective of this study was to assess the physicochemical and sensory changes of a kefir manufactured by a two-step fermentation (MTY, $1^{st}$ step: $37^{\circ}C$ for 9 h; $2^{nd}$ step: $24^{\circ}C$ for 15 h) and compare it with kefirs produced by two conventional methods (GTY, fermentation at $37^{\circ}C$ for 24 h; KEY, $22^{\circ}C$ for 24 h). Rapid changes in pH and titratable acidity (TA) were observed in samples from all three manufacturing methods during fermentation process and storage period. Lactic acid bacteria (LAB) counts of MTY increased gradually up to 12 h of fermentation, reaching 9.28 Log CFU/mL, with maximum value observed in this experiment of 9.48 Log CFU/mL. The LAB counts of all samples decreased significantly during storage. The highest viscosity was observed for MTY (1750-1771 cPs), compared with the lowest viscosity observed for KEY (1250-1277 cPs). The viscosity of all samples increased slightly during storage (1250-1805 cPs, p<0.05), as well as carbon dioxide content (0.01-1.36%, p<0.05), except for GTY. The most significant increase in alcohol concentration during storage period was seen in MTY from 0.01% to 1.36% (p<0.05). MTY scored significantly higher in most items of the sensory analysis, indicating that the product manufactured by the two-step fermentation method is more acceptable compared with conventionally produced kefirs.