• Korean Journal of Mineralogy and Petrology
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• v.33 no.4
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• pp.361-376
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• 2020

Atacamite and Verdigris were studied material scientific properties and durability that are used for traditional green pigment in traditional art painting work and Dancheong. As a result of ingrediant analysis, K-AA and K-VA identified Atacamite and Hoganite (or Verdigris) respectively. In order to find a factor of depressing the stability of pigment, we examined UV radiant exposure test, CO2/NO2 gas corrosion test and salt spray test. Salt spray test damaged both samples which were formed salt particle on the surface of the samples and it makes color disability. Furthermore, the results of gas corrosion test that both pigments change color enough to be perceived by the naked eyes showed that an air pollutant NO2 gas is also considered to be a major damage factor. In the case of K-VA, Hoganite that is main component of sample changes Tenorite with turn black after accelerated UV radiant exposure test. The consequences of the atmospheric environment effect test of the two pigments, K-VA showed relatetively weaker than K-AA.

• Journal of Microbiology and Biotechnology
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• v.26 no.4
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• pp.666-674
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• 2016

The bacterial strains were screened as potential starters for fermenting low-salt doenjang (a Korean traditional fermented soybean paste) using Korean doenjang based on proteolytic and antipathogenic activities under 6.5-7.5% NaCl conditions. Phylogenetic analysis based on 16S rRNA gene sequences showed that they all belonged to the genus Bacillus. Proteolytic and antipathogenic activities against Escherichia coli, Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, and Aspergillus flavus, as well as fibrinolytic, amylase, and cellulase activities of the 10 strains were quantitatively evaluated. Of these, strains D2-2, JJ-D34, and D12-5 were selected, based on their activities. The functional, phenotypic, and safety-related characteristics of these three strains were additionally investigated and strains D2-2 and D12-5, which lacked antibiotic resistance, were finally selected. Strains D2-2 and D12-5 produced poly-γ-glutamic acid and showed various enzyme activities, including α-glucosidase and β-glucosidase. Growth properties of strains D2-2 and D12-5 included wide temperature and pH ranges, growth in up to 16% NaCl, and weak anaerobic growth, suggesting that they facilitate low-salt doenjang fermentation. Strains D2-2 and D12-5 were not hemolytic, carried no toxin genes, and did not produce biogenic amines. These results suggest that strains D2-2 and D12-5 can serve as appropriate starter cultures for fermenting low-salt doenjang with high quality and safety.

• Preventive Nutrition and Food Science
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• v.11 no.2
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• pp.140-145
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• 2006

Seventy eight bacterial strains were isolated from several jeotgals using MRS and M 17 agar media. The probiotic properties such as tolerance of extreme growth condition, production of antimicrobial compound, production of hydrogen peroxide, and enzymatic activity of bile salt hydrolase were investigated. DHK 4, 10, 21 and 74 strains showed_a strong tolerance property against extreme conditions such as low pH and 0.5% oxgall-supplemented medium. DHK 10 and 47 strains produced hydrogen peroxide on TMB agar plate. DHK 8 and 10 strains produced antimicrobial compounds onto MRS agar against E. facalis. DHK 4, 6, 21, 29, 33, 63 and 87 strains had high activities of bile salt hydrolase. Especially, DHK 10 displayed a strong probiotic candidate; the abilities to produce the antimicrobial compound, hydrogen peroxide, and bile salt hydrolase. All these strains are assumed to be useful probiotic candidates. Among 78, twenty seven strains which have probiotic properties were tentatively identified by 16S rRNA sequencing. Among them, 7 Lactobacillus spp., 6 Leuconosotoc spp., 2 Weisella spp., 1 Pediococcus sp., 1 Staphylococcus sp., 1 Enterococcus sp. and 2 Streptococcus spp. were tentatively identified.

• Journal of Community Nutrition
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• v.8 no.4
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• pp.185-192
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• 2006

This study was performed to investigate factors affecting sensitivity and preference for salty tastes of Korean adult females. Sensitivity and preference for salty tastes were determined as detection threshold concentration of NaCl solution and the optimally-preferred NaCl concentration of the bean sprout soup, respectively. A self-administered questionnaire was used to obtain the information regarding general characteristics, self diagnosis of stress, health-related lifestyle practices, dietary habits and food preferences. Dietary intake using 24-hours recall and blood pressure were measured. Salty taste detection thresholds and optimally-preferred NaCl concentrations were 0.0197% and 0.357%, respectively. There was a significant positive correlation between the optimally-preferred salt concentration and age, despite no significant correlation between either sensitivity or preference for salty taste and sodium intake, which was 3,605mg/day. Those who had bread or cereal with milk as breakfast instead of a traditional Korean meal and those who preferred jjigae to soup had significantly higher NaCl preferences for bean sprout soup. Going to bed after midnight and skipping meals (${\geq}3/week$) decreased salty taste sensitivity without reaching statistical significance. Self awareness of one's own health, recent weight changes, family history of hypertension, sleep quality, getting-up time, rate of eating and other food preferences did not affect either perception. Stress level, TV watching, BMI and sodium intake did not have significant correlation to sensitivity or preference. Further research including a large number of well-controlled subjects and more accurate measurement of sodium intake should be directed to find other factors affecting salt preference and sensitivity in order to decrease Na intake and related diseases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.791-795
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• 1996

Toha-jeot(salt-fermented Toha shrimp) is a traditional fermented food in Korea. Toha-jeot is fermented for 90 days at $4\pm1^{\circ}C$ with 20%(w/w) salt per live Toha shrimp. We expect that the high polymer chitin of Toha shell will be hydrolyzed by chitinase during the fermentation of Toha-jeot and that the low molecular weight of chitin oligosaccharides will be produced. We experimented 7 samples which were taken at the interval of 15 days during the total 90 days of fermentation. We also measured molecular weight of Toha-chitin, viscosity and molecular weight distribution of chitin during fermentation of Toha-jeot, The decrease of viscosity and average molecular weight of chitin were observed as fermentation proceeds. Chitin oligosaccharide with $10^3molecular$ weight was low until 60 days fer-mentation. However, chitin oligosaccharide with $10^3molecular$ weight was high after 75 days fer-mentation. And chitin oligosaccharide with $10^2molecular$ weight were observed after fermenting Toha for 75 days and 90 days, but chitin oligosaccharide with 10'molecular weight did not appear up to 60 days of fermentation.ation.

• Food Science and Preservation
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• v.17 no.6
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• pp.800-806
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• 2010

The aim of this research is to develop recipe of kimchi beverage made of sun-dried salt. A distinction between this recipe with existing ones is the Korean traditional ingredient, sun-dried salt. The variety and amount of recruitment on the beverage was established after its characteristics were investigated by sensory tests. Preference of sweetening agent for the beverage was oligosaccharide > honey > sugar powder > sugar > aspartame > pear juice. While sensory evaluation was conducted on color, flavor and overall acceptance, the overall acceptance scores are as following; 6.24 for watery radish kimchi, 6.00 for white kimchi and 5.76 for Korean cabbage kimchi. Among other beverages, watery radish kimchi beverage was preferred. Amount of kimchi for the beverage was most suitable at 10 % of the contents. It was the same with all the other beverages. When the products were stored in normal temperature, the evaluation scores dropped for all sensory items as time passed.

• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.78-83
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• 2001

To use the by-products of whelk processing, whelk internal organ with the addition of bromelain were used to make jeotgal, Korean traditional salted and fermented seafood sauce. The products were prepared at different salt concentrations of 10, 15 and 20% with various bromelain contents 0, 0.01, 0.1 and 0.5%. The samples were stored at $10^{\circ}C$ and the chemical and microbiological analyses were evaluated for four weeks. The initial pH (near 6.1) in all conditions decreased in the beginning stage of aging, then gradually increased until three weeks and finally decreased to $5.6{\sim}6.0$. The sample with lower salt concentration showed less pH change For two weeks. The samples treated with higher bromelain in 10% and 15% salt concentration showed higher pH values after 4 weeks compared to the nontreated control. Amino nitrogen in the samples increased at lower salt concentration and at higher bromelain content. The amino nitrogen showed maximum value, 780 mg%, at 10% salt and 0.5% bromelain treatment. Total nitrogen contents increased with aging periods, especially increased rapidly in high concentrations of bromelain treated samples at early stages of aging. The higher salt concentrations in the product decreased the total microbial number and lactic acid bacterial number.

• Food Science and Preservation
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• v.14 no.3
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• pp.294-300
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• 2007

Three varieties of soy sauce were prepared using saps of bamboo, xylem and gorosoe, with sea salt and bamboo salt, in May. Soy sauce was fermented in the traditional manner. Homemade soy sauce was analyzed after 3 months of aging. The pH and amino-type nitrogen content of soy sauce fermented with xylem sap and sea salt were very high, and malic acid was dominant among four types of organic acid. The content of calcium in soy sauce fermented with bamboo sap and sea salt was fourfold greater than that of the control. The contents of total amino acids in the soy sauces fermented with xylem sap and gorosoe, with the addition of sea salt instead of water, were 2-fold and 1.4-fold greater than that of ordinary soy sauce, respectively. In the DPPH assay, the antioxidant effect of soy sauce fermented with bamboo sap and sea salt was higher than that of other samples. Sensory evaluation showed that the overall acceptability of soy sauce fermented with gorosoe and sea salt was best, among the samples tested.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.61-68
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• 2012

Sikhae is a traditional Korean fermented seafood with a 7-10% salt concentration. Consumers have begun to look for low-salt food because excess salt is known to cause hypertension and gastric cancer. The quality characteristics of low-salt squid sikhae were investigated at different fermentation temperatures and periods, so as to determine its shelflife. The shelf-life of the low-salt (5%) squid sikhae at $-1^{\circ}C$ based on pH was 142 days. The functional activities of the ethanol extract of squid sikhae such as its antioxidant activity and inhibitions on ${\alpha}$-glucosidase, ${\beta}$-glucuronidase, and elastase were stronger than those of the water extract. Based on the results of sensory evaluation, the low-salted squid sikhae was very similar to fermented seafood. In conclusion, low-salt sikhae is commercially viable.

• Journal of Life Science
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• v.9 no.4
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• pp.489-492
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• 1999

A bacteial strain which can produce the extracellular fibrinolytic enzyme was isolated from Jeot-Gal (anchovy) that was Korean traditional salt-fermented fish. The isolated bacterium was identified to be a strain of Bacillus sp. The optimal medium for fibrinolytic enzyme production was determined to consist of 5 g maltose, 10 g defatted soybean, 20 g sodium chloride, 1.75 g K2HPO4 per liter (pH 7.0)