• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1203-1208
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• 1998

To utilize astringent persimmon (Diospyros kaki, T.) effectively, response surface methodology (RSM) was applied to optimize and monitor the vinegar fermentation conditions by two stage fermentation. In the first stage, the fermentation conditions for maximum alcohol content was $20.51\;^{\circ}brix$ in sugar concentration of astringent persimmon, 139.52 rpm in agitation rate, and 94.88 hr in fermentation time. When sugar concentration of astringent persimmon was $14\;^{\circ}brix$, maximum alcohol content predicted by response surface methodology was 7.1% at agitation rate of 40 rpm and fermentation time of 120 hr. In the second stage, the fermentation conditions for maximum acidity was 224.40 rpm in agitation rate, 176.07 hr in fermentation time. Alcohol content and acidity predicted at the optimum conditions were similar to experimental values.

• The Korean Journal of Food And Nutrition
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• v.36 no.5
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• pp.360-367
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• 2023

The major active components of Astragalus membranaceus (AM) are isoflavones, which exist in the form of various glycosides. Nuruk is a traditional fermentation starter in Korea, and is suitable for the biotransformation of isoflavone glycosides because it contains various microorganisms and enzymes. This study was performed to determine changes in the isoflavones and antioxidant properties of AM fermented (AF) with nuruk over 24 hours. AF was sampled after 0, 2, 4, 6, 12, 18, and 24 h of fermentation, and calycosin 7-glucoside, ononin, calycosin, and formononetin content, and the antioxidant properties of AF were analyzed. The total phenolic content increased with fermentation time, and the ABTS radical scavenging activity increased until 6 h of fermentation and then decreased. During fermentation, the isoflavone glycosides decreased significantly as fermentation time increased. The contents of calycosin and formononetin, which are aglycons of calycosin-7-glucoside and ononin, increased from 100.54 ㎍/g to 276.84 ㎍/g and from 56.29 ㎍/g to 123.04 ㎍/g, respectively, at 18 h of fermentation. Significant correlations were observed between fermentation time, isoflavone content, and antioxidant properties. The results of this study showed that fermentation with nuruk is suitable for the biotransformation of isoflavones in AM.

• Journal of the East Asian Society of Dietary Life
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• v.27 no.3
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• pp.341-347
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• 2017

This study was carried out to investigate the characteristics and Vitamin $K_2$ (MK-7) productivity of Cheonggukjang fermented by Bacillus subtilis SRCM100757 depending on the inoculum concentration 0.5% (v/w), 1% (v/w) and 2% (v/w). The lowest moisture content and water activity were $53.7{\pm}0.6%$ and $8.39{\pm}0.09$ after fermentation for 72 hours at 2% (v/w). pH slowly became alkalized during fermentation, but there was no significant difference. Amino nitrogen content increased with time and the highest content was $580.8{\pm}1.9mg%$ after fermentation for 72 hours at 2% (v/w). Lightness (L value) and yellowness (b value) decreased with time, whereas redness (a value) hardly changed. MK-7 contents increased with time at each inoculum concentration. The highest content was $20.47{\pm}1.53$ after fermeatation for 72 hours at 2%(v/w) and there were no significant differences between 1%(v/w) and 2%(v/w) inoculum concentrations.

• 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.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.184-191
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• 1995

This study was designed to investigate the changes In chemical characteristics of traditional kochujang increase in fermentation time, whereas that of total sugar decreased rather rapidly during aging of meju. Amino nitrogen content of meju Increased sharply up to 40 days of fermentation and then decreased there after On the other hand, ammoniacle nitrogen content continued to increase with increasing aging time. Initially, maltose was the most abundant free sugar, but was later replaced by glucose or fructose as the fermentation proceeded. Among non-volatile organic acids, pyroglutamic acid was present at an appreciably other organic acids did not change considerably during fermentation. The total free amino acid content Increased up to 40th day of aging and then decreased thereafter The was the most abundant amino acid followed in decreasing order by Try and Glu in meju fermented for 40 days.

• Food Science of Animal Resources
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• v.25 no.2
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• pp.226-231
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• 2005

This study was carried out to find the physico-chemical attributes of yogurt base with Lactobacillus case; 00692 during 72 hr fermentation at $37^{\circ}C$. The pH decreased up to 44 hr and plateaued thereafter, and the titratable acidity increased up to 40 hr. The number of lactic acid bacteria sharply increased with $1.0\times10^7cfu/mL$ up to 48 hr of fermentation and slowly increased thereafter. The free amino acids produced during the fermentation reached the maximum value at 40 hr and gradually decreased thereafter. In the result of electrophoresis, the band was the thickest at 44 hr and mostly disappeared at 72 hr fermentation. The present data showed that the range of optimum fermentation time for yogurt base using Lactobacillus casei 00692 was from 40 to 44 hr.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.356-362
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• 1998

The study is to predict fermentation time of Korean style soybean paste by portable electronic nose that has six metal oxide sensors. Korean style soybean paste using Aspergillus oryzae was fermented at $15^{\circ}C,\;20^{\circ}C\;and\;25^{\circ}C$. The changes of sensitivity by electronic nose, amino nitrogen and reducing sugar were observed during fermentation. Sensitivities of six metal oxide sensor were decreased with increase of fermentation time while amino nitrogen was increased. Sensor #3 and #4 showed good correlation between sensitivities of the sensors and fermentation time $(r^2=0.71{\sim}0.95)$. And the good correlation between sensitivity by electronic nose and the produced amino nitrogen was shown until soybean paste was fermented. Portable electronic nose using metal oxide sensor (#3 and #4) could predict fermentation time of Korean style soybean paste.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.504-510
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• 2003

To optimize the preparation process of Jeung-Pyun, an experiment was derived, using a central composite design, to fmd the optimal mixing conditions. The addition of Paecilomyces japonica powder, the volume of Tak-Ju and the second fermentation time were independent variables, with the pH, volume, color, sensory and texture properties of the Jeung-Pyun selected as response variables. As the Paecilomyces japonica powder and fermentation time were increased, the b values and volume after the second fermentation also increased. The color of the Jeung-Pyun became deeper with increases in the Paecilomyces japonica powder and fermentation time, and was deepest on the addition of 30% Tak-Ju. The pH increased with increasing fermentation time of the Jeung-Pyun, and on the addition of 3% Paecilomyces japonica rapidly increased more than with the other groups. The optimal mixing conditions for the best quality Jeung-Pyun, with restricted conditions above a b value of 3, a color intensity above 3, and a volume of 40mQ and a pH of 4.02-4.04 after the second fermentation, were 4.0%, 20% and 45 mins for the Paecilomyces japonica powder, Tak-Ju and second fermentation time, respectively.

• Journal of the Korean Society of Food Culture
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• v.9 no.1
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• pp.79-85
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• 1994

This study was conducted to determine the optimum conditions for the preparation of traditional Korean whole cabbage Kimchi with salted shrimp. Sensory, physical and chemical characteristics of Kimchi with various salted shrimp level(1.8, 3.6%), fermentation time(12, 24, 36 hrs) and storage period(1, 4, 7 days) were measured. As the fermentation time and storage day were extended, pH of Kimchis decreased but titratable acidity of Kimchis increased. The more salted shrimp in Kimchi resulted in the higher titratable acidity. The longer fermentation time and the longer storage resulted in the more citric, malic and succinic acid, and the less lactic and acetic acid in Kimchi. The optimum conditions for the preparation of Korean whole cabbage Kimchi were 3.6% salted shrimp level, 12 hours fermentation time and 84 hours(3.5 days) storage period.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.855-861
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• 2015

Lactobacillus plantarum is used for fermentation of fish products, meat and milk. However, the utilization of these bacteria in egg processing has not been done. This study was designed to evaluate the potential of fermented egg albumen as a functional food that is rich in angiotensin I-converting enzyme inhibitors activity (ACE-inhibitor activity) and is antihypertensive. A completely randomized design was used in this study with six durations of fermentation (6, 12, 18, 24, 30, and 36 h) as treatments. Six hundred eggs obtained from the same chicken farm were used in the experiment as sources of egg albumen. Bacteria L. plantarum FNCC 0027 used in the fermentation was isolated from cow's milk. The parameters measured were the total bacteria, dissolved protein, pH, total acid and the activity of ACE-inhibitors. The results showed that there were significant effects of fermentation time on the parameters tested. Total bacteria increased significantly during fermentation for 6, 12, 18, and 24 h and then decreased with the increasing time of fermentation to 30 and 36 h. Soluble protein increased significantly during fermentation to 18 h and then subsequently decreased during of fermentation to 24, 30, and 36 h. The pH value decreased markedly during fermentation. The activities of ACE-inhibitor in fermented egg albumen increased during fermentation to 18 h and then decreased with the increasing of the duration of fermentation to 24, 30, and 36 h. The egg albumen which was fermented for 18 h resulted in a functional food that was rich in ACE-inhibitor activity.