• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1843-1851
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• 2014

This study evaluated the quality characteristics and antioxidant activities of barley Doenjang (soybean paste) containing various contents (4, 12, and 20%) of kelp extracts. After 60 days of fermentation, pH, acidity, and viscosity of Doenjang were 5.80~6.86, 0.57~1.87%, and 4,913.3~9,333.3 cps, respectively, showing significant differences according to content of kelp extracts. Amino-type nitrogen contents was 902.60~921.90 mg%. For color values, L and b values increased significantly (P<0.001), whereas a value decreased slightly according to kelp extracts. DPPH radical scavenging effect ($IC_{50}$) for butylated hydroxyanisole ranged from 10.28 mg/mL to 23.23 mg/mL. DPPH radical scavenging effects of control was highest among the samples. The total polyphenol and flavonoid contents were 12.72~6.37 mg tannic acid equivalence/g, and $0.98{\sim}1.56{\mu}g$ rutin equivalence/g, respectively. Initial counts of total bacteria and lactic acid bacteria were 7.20~7.57 log CFU/g, and 4.20~4.71 log CFU/g respectively, showing significant difference according treatment and fermentation (P<0.05). In the sensory evaluation, 20% kelp extract Doenjang (5.6) showed higher overall acceptability than other samples (6.5) (P<0.01). Especially, umami taste (6.1) and texture (6.4) of 20% kelp extract Doenjang were higher than those of control (P<0.05). These results suggest that Doenjang containing kelp extracts, will be good for industrial fields.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.784-791
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• 2013

Four different yeasts (Fermivin (FM), Saf-instant yeast red (SI), Angest wine active dry yeast (AW) and Angest instant yeast high sugar (AI)) were used for the fermentation of black raspberry wine. The amount of reducing sugars in FM (2.7%) and AI (2.8%) were higher than those in SI (2.4%) and AW (2.5%). The amount of glucose (the major free sugar) was higher in AW (2.57 mg/mL) and AI (2.50 mg/mL) than FM (2.03 mg/mL) and SI (1.75 mg/mL). AW (11.95%) had the highest alcohol content, while SI (11.75%) had the lowest. The pH of FM (pH 3.73) was the lowest, and there were no significant differences in total acidity among the samples. The major organic acid in the wines was citric acid (6.71~8.18 mg/mL) and the amount of organic acids depended on the type of yeasts. The amount of malic acid was highest in SI (2.92 mg/mL), and lowest in AI (1.83 mg/mL). The Hunter color test showed that SI was highest in lightness, redness and yellowness, whereas AI was lowest. There were no differences in turbidity between the samples. There were no significant differences in total phenolic contents (TPC) and total anthocyanin contents (TAC). However, the TPC and TAC of black raspberry wines were higher than those in commercial red wines. The antioxidant activities of wines (determined by ABTS and FRAP) increased in the order of FM, AI, AW and SI. It could not be concluded which yeast is adequate for the fermentation of black raspberry wine because any of the tested yeasts showed the best in all the quality characteristics of the wines.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.12
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• pp.1832-1838
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• 2010

The objective of this study was to improve the flavor of Cheonggukjang prepared by the culture optimization of starter with the fibrinolytic activity. After 25 strains isolated from the commercial Cheonggukjang and Doenjang in different regions were compared, 7 Bacillus strains with proteolytic and slime-producing activities were selected. When the fibrin plate method for fibrinolytic activity was applied, CJJN-4 and 5 showed the higher activity in tripticase soy broth (TSB). All Cheonggukjang prepared with CJJN-4 and 5 also had the fibrinolytic activity, regardless of culture temperature or time. Especially, Cheonggukjang prepared at $40^{\circ}C$ showed higher activity than $45^{\circ}C$, and Cheonggukjang prepared with CJJN-4 for 48 hr at $40^{\circ}C$ showed the highest fibrinolytic activity. Although there was no significant difference in pH of Cheonggukjang prepared with CJJN-4 or 5 during 72 hr at $40^{\circ}C$, Cheonggukjang prepared with CJJN-4 at $45^{\circ}C$ had lower pH until 60 hr than $40^{\circ}C$ or CJJN-5. The total amino type nitrogen contents of Cheonggukjang were 1,139.6 (CJJN-4) and 1,027.6 mg% (CJJN-5) for 72 hr at $40^{\circ}C$, and their producing rates were also higher at $40^{\circ}C$ fermentation than $45^{\circ}C$. Meanwhile, the contents of ammonia type nitrogen induced unpleasant flavor were lower in Cheonggukjang with CJJN-4 and 5 at $40^{\circ}C$ than CJJN-5 at $45^{\circ}C$. Therefore, Cheonggukjang fermented with CJJN-4 starter at $40^{\circ}C$ had the improved flavor, such as change of amino or ammonia type nitrogen production, and higher fibrinolytic activity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.720-728
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• 2014

In order to characterize the quality of Doenjang, fermented Korean soybean paste, subjected to long-term aging, this study performed physico-chemical analyses and sensory evaluation according to aging period (from 1 to 9 years). Regarding the proximate composition of Doenjang according to aging period, moisture, crude protein, crude lipid, crude ash, and salt contents showed little differences among Doenjang samples. Amino-type nitrogen content was 1,046.7 mg% in the 1 year-aged sample, 990.9~996.9 mg% in the 2~5 year-aged samples, and 1,214.1~1,304.8 mg% in the samples fermented more than 5 years. ${\Delta}$E value, reflecting total color differences between the samples, increased according to aging period. Ratios of linoleic and linolenic acids, which are essential fatty acids in soybeans, constituted 55% of total fatty acids, which was the most abundant among all fatty acids. The major free sugar in Doenjang was fructose at a content of 1.6~2.2% in 1~9 year-aged Doenjang. Glycoside form of isoflavones in Meju constituted 77.1%, and the aglycon form constituted 22.9%. However, the glycoside type of isoflavones in soybeans was converted to aglycon type in Doenjang through fermentation and aging. In the sensory evaluation of Doenjang samples, brown color, salt smell, soy sauce flavor, and viscosity all increased according to aging period, whereas sweet flavor, roast smell, beany flavor, salty taste, and acrid taste showed no significant differences. In cluster analysis of the sensory attributes of Doenjang according to aging period, 1 year-aged Doenjang was significantly different between 2 year- and 3~5 year-aged Doenjang.

• Microbiology and Biotechnology Letters
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• v.26 no.3
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• pp.250-256
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• 1998

D-Tagatose production from D-galactose was investigated using 35 type strains of American Culture Type Collection (ATCC) and Korean Collection for Type Cultures (KCTC) which have potential to produce D-tagatose. Enterobacter agglomerans ATCC 27987 was selected as a D-tagatose producing strain due to its short fermentation time and high production of D-tagatose. Optimization of the culture conditions for D-tagatose production by E. agglomerans ATCC 27987 was performed. Among various carbon sources, D-galactose was the most effective carbon source for D-tagatose production. As the D-galactose concentration was increased, cell growth and D-tagatose production increased. Effect of nitrogen sources on D-tagatose production was studied. Of inorganic nitrogen sources, ammonium sulfate was effective one for D-tagatose production and yeast extract was the most suitable organic nitrogen nutrient. The concentrations of inorganic compounds such as KH$_2$PO$_4$, K$_2$HPO$_4$, and MgSO$_4$$.$7H$_2$O were also optimized for D-tagatose production. The optimal medium was determined to contain D-galactose of 20 g/l, yeast extract of 5.0 g/l, (NH$_4$)$_2$SO$_4$ of 2.0 g/l, KH$_2$PO$_4$ of 5.0 g/l, K$_2$HPO of 5.0 g/l, and MgSO$_4$$.$7H$_2$O of 5 mg/l. The optimal environmental conditions in a 250-$m\ell$ flask were found to be pH of 6.0, temperature of 30$^{\circ}C$, and agitation speed of 150 rpm. D-tagatose of 0.41 g/l could be obtained in 24 h from 20 g/l D-galactose at the optimal culture condition without induction and cell concentration.

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.3
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• pp.487-494
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• 1992

This experiment was conducted to study the effect of addition of Lucerne juice (LJ) obtained by mechanical extraction of freshly harvested crop on the nutritive value of rice straw silage. Rice straw (RS) was ensiled with intact, NaOH or $NH_3$ treated LJ at 3:7 ratio on fresh weight basis (LJ RS, LJ NaOH RS and LJ $NH_3$ RS, respectively). Each alkali was mixed with fresh juice at a level of 4% of rice straw dry matter just before ensiling. Rice straw ensiled with water was prepared as the control (W RS). In the digestion trial, goats were allocated in a $4{\times}4$ Latin-square design and fed the diet containing three parts of RS silage and one part of wheat bran (DM basis). For the goats receiving the control silage, urea was supplemented at feeding time so as to adjust the nitrogen intake except for goats on LJ $NH_3$ RS silage. Crude protein content of RS silage was increased from 5.2 to 9.1% (DM basis) by the addition of intact LJ and to about 24% by $NH_3$ treated LJ. The control W RS silage contained only trace amount of lactic acid and was dominated by acetic and butyric acid. The addition of intact LJ reduced butyric acid content and $NH_3-N/TN$ of the silage whereas the addition of alkalized LJ increased those values and shifted to a butyrate type fermentation. Nutrient digestibilities and nitrogen balance of goats were almost the same when they were fed W RS and LJ RS silage indicating the addition of intact LJ did not improve the nutritive value. The addition of alkalized LJ significantly increased the fiber digestibilities of RS silage and $NH_3$ treatment was more effective than NaOH treatment. Postprandial ruminal $NH_3-N$ and blood urea nitrogen (BUN) concentrations were decreased by feeding LJ NaOH RS silage suggesting ruminal protein synthesis was enhanced along with the increase of energy supply for supply for rumen microbes by the alkali treatment. The advantageous fiber digestibilities of LJ $NH_3$ RS silage compared with those of LJ NaOH RS silage might be attributable to a sufficient nitrogen supply for microbial fiber digestion in the rumen.

• Korean Journal of Environmental Agriculture
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• v.38 no.4
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• pp.262-268
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• 2019

BACKGROUND: To investigate mineralization characteristics of organic resources in the soil, five materials (rice straw, cow manure sawdust compost, microorganism compost, mixed oil-cake, and amino acid fertilizer) were treated according to the nitrogen content, and an indoor incubation experiment was conducted for 128 days. The results of this analysis were applied to determine the nitrogen mineralization pattern of these organic resources. METHODS AND RESULTS: During the constant temperature incubation period, the nitrogen net mineralization rate of the organic resources was the highest in the amino acid fertilizer with the highest nitrogen content, and the lowest in the rice straw with the lowest nitrogen content. A positive correlation (0.96) was observed between the potential nitrogen mineralization rate and total nitrogen content. The mineralization rate constant, k, was negatively correlated with the organic matter (-0.96) and carbon content (-0.97). The nitrogen mineralization rate during the first cropping season, as estimated by the model, was 6.6%, 11.6%, 30.9%, 70.7%, and 81.0% for the rice straw, the cow manure sawdust compost, the microorganism compost, the mixed oil-cake, and the amino acid fertilizer, respectively. CONCLUSION: The nitrogen mineralization rate varies depending on the type of organic resources or the nitrogen content; thus, it can be used as an index for determining the nitrogen supply characteristics of the organic resource. Organic resources such as compost with low nitrogen content or those undergoing fermentation contain organic nitrogen. Organic nitrogen is stabilized during the composting process. Therefore, as the nitrogen mineralization rate of these resources is lower than that of non-fermented organic resources, it is desirable to use the fermented organic materials only to improve soil physical properties rather than to supply nutrients for the required amount of fertilizer.

• Journal of Animal Environmental Science
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• v.11 no.3
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• pp.169-176
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• 2005

The farm house structure, ventilation system and manure treatment of two-storey buildings and sawdust pig houses were surveyed and analyzed. Based on the data for ten selected farms in five provinces during eight months, the goal is to eventually establish a standard two-storey pig house. Manure treatments were composting, slurry and activated sludge in two-storey pig houses, while fermentation method was done in sawdust pig house. The depth of sawdust as a litter material were 10 to 60cm, with a duration of 1/2, 1, 3 and 6 months, respectively. The ventilation systems were the mechanical type in two-storey pig houses and natural system in the sawdust pig house. Side wall in the two-storey pig house was enclosed with insulation materials such as block, colored metal sheet and sandwich panels. The minimum ceiling height in the first floor of the two-storey pig house was 2.0m and the maximum was 3.0m. On the second floor, ceiling height ranged from 2.0 to 2.7m. The construction cost in the two-storey systems were $700\~140$, and sidewall curtain systems were $30\~40$ thousand Won/pyung.

• The Korean Journal of Ecology
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• v.27 no.5
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• pp.291-300
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• 2004

This study was carried out to investigate the relationship of occurrence and distribution of Eupatorium rugosum by forest types and soil characteristics in Mt. Namsan in Seoul, Korea. E. rugosum is designated as a harmful non-indigenous plant in ecosystem by the Natural Environment Conservation Act in Korea. E. rugosum grew along roadside and in valleys with some favorable light conditions. E. rugosum occurred in aggregations under Pinus densiflora and Robinia pseudoacacia communities. And it was sparse in forests of Quercus mongolica and P. koraiensis. The representative herb layer species were Oplismenus undulatifolius, and Parthenocissus tricuspidata in the E. rugosum communities. There was a significantly negative correlation between the coverage of E. rugosum and the coverage of tree layer. However, the result of ANOVA of E. rugosum coverage by dominant species of tree layers did not show a significant difference (p>0.05). The level of soil moisture content, organic content, and pH, was slightly higher in communities with E. rugosum than without, but it was statistically non-significant difference. However, it was found that the coverage of E. rugosum was very significantly negative correlated with the depth of top soil profile (litter and fermentation layer, p<0.05).

• Korean Journal of Food Science and Technology
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• v.19 no.3
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• pp.231-238
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• 1987

Two kinds of soy pastes with different colors (reddish brown and yellowish white) were dehydrated by freeze drying in powder form. Hygroscopic behaviors of powdered soy pastes were investigated under the conditions of various water acitivities (0.11-0.88) and three different temperatures (25,40 and $50^{\circ}C$), and presented a kinetic and thermodynamic interpretatons in the view point of qualities and storage stability. Moisture absorption isotherms of powdered soy pastes were of type II according with BET classification and can be described by the Henderson's empirical equation. The safe storage moisture levels calculated by the Laurie's equation were ranging from 5.5 to 3.98% dry basis with oaring temperatures. The moisture absorption process for powdered soy paste followed the Ist order kinetic in the difference of equilibrium moisture content and arbitrary moisture content and the initial step was characterized by very fast absorption of moisture. The change of, dispersion capacity and color difference for powdered soy paste were extremely dependent upon water activity under the storage and the maximum stability was found at safe storage moisture levels. Also, the variation of thermodynamic parameters with moisture content was significant at safe storage moisture content levels and suggested d the considerable correspondence to storage stability of powdered soy paste.