• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.12
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• pp.1503-1510
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• 2007

This study was carried out to investigate antioxidant substances (phenolic compounds and brown pigment), antioxidative effect and nitrite scavenging ability (NSA) of solvent extracts (hexane: HE, methanol; ME, water: WE) from fermented soybean foods, Chungkukjang and Doenjang. The antioxidant activities were determined by the measurements of peroxide value (POV) on the linoleic acid system, electron donating ability (EDA) and superoxide dismutase (SOD)-like activity. The contents of phenolic compounds and total brown pigments in Doenjang were $28.5{\pm}0.3mg/100g$ and optical density (OD) $1.98{\pm}0.03$, respectively, whereas their contents in Chungkukjang were significantly lower with $5.8{\pm}0.3mg/100g$ and OD $0.95{\pm}0.02$. The brown pigment contents of hydrophilic extracts increased more than that of lipophilic extracts through the fermentation and ripening processes. The ME of Doenjang exhibited higher inhibitory effects against the peroxidation of a linoleic acid system than that of Chungkukjang. The EDA and NSA of MEs were higher than those of WEs. Among the MEs, Doenjang showed the highest levels of EDA and NSA. On the other hand, the SOD-like activities of WE were higher than those of ME at the same concentrations and their activities of Doenjang were significantly higher than that of Chungkukjang. In conclusion, the antioxidative effects and NSA of Doenjang was significantly higher than those of Chungkukjang. It seemed that phenolic compounds and brown pigments formed during fermentation and ripening partly affect the antioxidative activities of fermented soybean foods.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.11
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• pp.1619-1625
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• 2012

The purpose of this study is to determine long-term storage conditions for winter kimchi. Kimchi was stored in a kimchi refrigerator for 6 months with or without fermentation. Four different temperature systems used were as follows: 5 days at $10^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F1), 1 day at $15^{\circ}C$ followed by storage at $-2.5^{\circ}C$ (F2), storage at $-1^{\circ}C$ (S1), or at $-2.5^{\circ}C$ (S2). Time periods required for F1, F2, S1, or S2 kimchi to reach pH 4.4 and acidity 0.6% were 2, 8, 12, and 22 weeks, respectively. Lactobacillus spp. growth on F1 and F2 kimchi was faster and greater than that on S1 and S2 kimchi, revealing a maximum concentration of 8~9 verses 6.8 log CFU/mL, respectively. However, Leuconostoc spp. were fully grown (8~9 log CFU/mL) on all four kimchi samples regardless of temperature, even at $-2.5^{\circ}C$, although the times required to reach maximum growth were different. Growth of Lactobacillus and Leuconostoc spp. both decreased after reaching maximum levels, except for F1 kimchi. Sensory evaluation results for 3 month storage showed that F1 kimchi was the best among kimchi samples in terms of appearance, acidic taste, carbonated taste, crispiness, and moldy smell. For 6 months of storage, F1 and S1 kimchi were the most highly evaluated among the kimchi samples. Sensory evaluation result for S1 kimchi stored at $-1^{\circ}C$ was comparable to that of F1 kimchi due to fully grown Leuconostoc spp. Acidities of F1 and S1 kimchi after 6 months of storage were 0.8 and 0.7%, respectively. Taken together, fermentation of kimchi at $10^{\circ}C$ for 5 days followed by storage at $-2.5^{\circ}C$ for 6 months was optimal for high quality kimchi. Sensory properties of winter kimchi were significantly influenced by the degree of fermentation.

• Food Science and Preservation
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• v.12 no.6
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• pp.613-616
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• 2005

The aging degree of Kimchi fermented at $4^{\circ}C$ for 29 days was evaluated by the correlation between the flavor and the acidity analysis. The Kimchi fermentation induced a gradual reduction in pH and an increase in acidity from $0.26\%$ (initial) to $1.15\%$ (29th day). Flavor pattern of the fermented Kimchi was obtained by the electronic nose system with 12 metal oxide sensors. Electronic nose analysis could differentiate the flavor profiles of Kimchi according to the fermentation periods, making 5 group in the principal component analysis (PCA) plot Therefore, aging degree of Kimchi could be differentiated by flavor patterns analysed by electronic nose.

• Current Research on Agriculture and Life Sciences
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• v.32 no.1
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• pp.30-33
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• 2014

A simulation model was developed to monitor food contamination during the ripening process of Kimchi on a factory scale. The cabbages were divided into three groups: control (without salt or red pepper), samples with added salt, and samples with added salt and red pepper. The processed Kimchi was left to ripen in a refrigerator at $4^{\circ}C$ and five frog heads (contaminant) left on the surface of the cabbages in each group. For the control, the contaminant exhibited a long life span of 10 days or more, however, for the samples with salt and samples with salt and red pepper, the contaminant showed a relatively short life span. In particular, for the processed Kimchi that included salt and red pepper, the life-span of the contaminant was dramatically decreased to around 3 days. Therefore, the present results suggest that the proposed simulation trial is suitable for monitoring contamination during Kimchi production. Moreover, since the contaminant could not survive more than 3 days, this suggests that the salt concentration in the Kimchi damaged the permeability of the skin and other tissue membranes.

• Journal of Life Science
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• v.12 no.5
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• pp.523-527
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• 2002

This study was carried out to investigate that physiologiral activity was relevence to mocroorganism and contents of sinigrin in Dolsan Leaf Mustard Kimchi (DLMK) during fermentation. DLMK was prepared from Dolsan leaf mustard, green onion, garlic, red pepper powder, ginger and salt. And it was fermented at 2$0^{\circ}C$ for 50days. The number of total microbes were increased until reaching the optimum ripening period and after, that number slowly decreased. And that tendency was agreement with antioxidative activity, And also the contents of sinigrin was increased until the optimally ripened time, then decreased. These results suggests that microorganism was significantly related to the physiological activity, and sinigrin was the one of the physiological active substances by microorganism in DLMK. In particular, 50days fermented DLMK at 2$0^{\circ}C$ was showed the highest contents of crude protein. Coincidently, 50days fermented DLMK might possibly contain high levels of crude proteins produced by various microorganism.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.8
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• pp.1094-1097
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• 2007

Vibration at frequency of 20 Hz and 0.18 g of acceleration was applied to 600 g watery kimchi contained in a glass jar of 1 L at subfreezing temperature (-3 and $-6^{\circ}C$) and $10^{\circ}C$ in order to see its effect on freezing and fermentation behaviors, respectively. The vibration at the subfreezing temperature delayed the freezing process and contributed to maintaining small ice crystal slurry in subsequent frozen storage. The vibration at $10^{\circ}C$ accelerated the acid and carbon dioxide production from the watery kimchi, which may be beneficial in shortening ripening time and attaining fresh cool taste.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.101-107
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• 1993

Zygosaccharomyces rouxii is a salt-tolerant yeast which plays an important role during the ripening stage of soy sauce fermentation. Z. rouxii used in the experiment could grow in YPD (1 % yeast extract, 2% peptone and 2% glucose, pH5.0) medium with 18% (w/v) NaCl, whereas Saccharomyces cerevisiae could only grow in YPD medium with less than 8% NaCl. In the presence of 15% NaCl, Z. rouxii accumulates a large amount of glycerol as a compatible solute within the cells in the exponential phase. It is a characteristic of salt-tolerant yeasts. From the chemical analyses on membrane lipid fluidity, the membrane structure of the cells grown in 15% NaCl was suggested to become more rigid and its fluidity was decreased to keep glycerol within the cells in response to surrounding medium with high concentrations of salt.

• Korean Journal of Food Science and Technology
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• v.49 no.2
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• pp.132-140
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• 2017

Nuruk, a traditional Korean alcoholic beverage starter, was evaluated as an additional saccharifying agent comprising up to 1.5% (w/w) of malt weight in ale-type beer processing. Sample characteristics were monitored during fermentation, ripening, and storage. Beer containing nuruk showed higher numbers of total viable bacteria and yeast cell counts. Additionally, ethanol (6.19-6.35%), color (Standard Reference Method), foam stability ($228.49-368.24{Sigma}$), saccharogenic power (307-417), and reducing sugar (3.83-5.25%) increased as the amount of nuruk was increased, while viscosity (3.13-2.07 cP) and bitterness unit (19.68-13.13) were lower than in samples without nuruk. Overall acceptance and aftertaste of the beer were significantly higher in a preference test. These results demonstrate that nuruk can be used to produce a new type of ale.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.3104-3104
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• 2001

The research described here was undertaken with the aim of monitoring, optimizing and ultimately controlling the production of heterofermentative microbes used as starters in the salami industry. The use of starter cultures in the fermented meats industry is a well-established technique used to shorten and standardize the ripening process, and to improve and control the organoleptic quality of the final product. Starter cultures are obtained by the submerged cultivation of suitable microorganisms in stirred, and sometimes aerated, fermenters where monitoring of key physiological parameters such as the concentration of biomass, substrates and metabolites suffers from the general lack of real-time measurement techniques applicable to aseptic processes. In this respect, the results of the present work are relevant to all submerged fermentation processes. Previous work on the application of on-line NIR spectroscopy to the lactic acid fermentation (Dosi et al. - Monreal NIR1995) had successfully used a system based on a measuring cell included in a circulation loop external to the fermenter. The fluid handling and sterility problems inherent in an external circulation system prompted us to explore the use of an in-line system where the NIR probe is immersed in the culture and is thus exposed to the hydrodynamic conditions of the stirred and aerated fluid. Aeration was expected to be a potential source of problems in view of the possible interference of air bubbles with the measurement device. The experimental set-up was based on an in-situ sterilizable NIR probe connected to the instrument by means of an optical fiber bundle. Preliminary work was carried out to identify and control potential interferences with the measurement, in particular the varying hydrodynamic conditions prevailing at the probe tip. We were successful in defining the operating conditions of the fermenter and the geometrical parameters of the probe (flow path, positioning, etc.) were the NIR readings were reliable and reproducible. The system thus defined was then used to construct and validate calibration curves for tile concentration of biomass, carbon source and major metabolites of two different microorganisms used as salami starters. Real-time measurement of such parameters coupled with the direct interfacing of the NIR instrument with the PC-based measurement and control system of the fermenter enabled the development of automated strategies for the interactive optimization of the starter production process.

• Food Science and Preservation
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• v.15 no.2
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• pp.293-299
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• 2008

Bacillus sp. SP-KSW3 is an auxothroph bacteria that is being used for starter in fermentation. Physico-chemical characteristics, enzyme activities, ACE inhibitor and antimutagenicity in fermented soybean (Kanjang) inoculated with Bacillus sp. SP-KSW3 starter was investigated for the ripening duration of fermentation. Tyrosinase and ACE showed 7% higher activity degree on the Kanjang maturated fermented 2 years with Bacillus sp. SP-KSW3 (Type I) than test field than Kanjang maturated 2 years (control). For antimutagenicity using S. enterica serovar Typhimurium TA100 against MNNG and NPD showed 35.17% and 28.37% (Type I). Similarly, S. enterica serovar Typhimurium TA98 was used against NPD and NQO showed 25.48% and 21.64% (Type I), respectively. Hydrogen donating ability 2 year for maturing (Type I) appeared most highly in the test eulogy 83.1% which it makes. Daidzin of isoflavone in fermented soybean showed similarly. Genistein was not detected The initial test field for daidzin and genistein contained 3.95 mg/kg and 1.25 mg/kg (Type I), respectively.