• Journal of the Korean Society of Food Science and Nutrition
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• 제43권5호
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• pp.756-762
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• 2014

This study evaluated the quality characteristics of soybean fermented with several Bacillus sp., which were selected based on their high enzymatic and antimicrobial activities. Total aerobic bacterial counts of fermented soybeans with HJ5-2 ($3.00{\times}10^9CFU/mL$) were the highest among all strains. Lactic acid bacteria numbered $2.50{\times}10^2{\sim}7.30{\times}10^4CFU/mL$ in soybeans fermented with isolates. Amylase and protease activities of the RD7-7 sample were the highest among all strains. Reducing sugar and amino-type nitrogen contents of fermented soybeans with HJ18-4 (2.35%) and RD7-7 (227.96 mg%) were the highest. Total amino acid contents of the samples were 16.62~18.38%, and glutamic acid, aspartic acid, leucine, lysine, arginine were major amino acids. Oxalic acid (36.51~63.57 mg/100 g) and succinic acid (429.49~600.15 mg/100 g) were the predominant organic acid. These results provide useful information for development starter (single and complex) as well as for the production of high quality fermented soybean foods.

• Journal of the Korea Academia-Industrial cooperation Society
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• 제20권12호
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• pp.340-347
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• 2019

This study investigated the brewing properties of rice beer made with yeast isolated from traditional whole wheat nuruk. The experimental method was followed by alcohol fermentation and quality analysis for six months after separating the yeast from nuruk. The yeasts isolated from traditional nuruk showed normal fermentation characteristics, like those of commercial yeast, in terms of alcohol production capability, sugar content, and pH reducing power. Especially, the yeast (KCCM 301) isolated from whole wheat nuruk showed higher contents of glycogen and trehalose than that of commercial yeast, and so KCCM 301 yeast has excellent yeast vitality. Meanwhile, the yeast (KCCM 90301) isolated from traditional Nuruk produced significantly higher alcohol and ester contents than that of commercial yeast. This has a positive effect for supplementing the taste and aroma of rice beer. In conclusion, the yeasts isolated from whole wheat nuruk showed the general alcohol fermentation pattern and aroma content of rice beer. These yeasts seem to be effective in strengthening the flavor of rice beer.

• Korean journal of food and cookery science
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• 제28권6호
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• pp.865-870
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• 2012

This study was performed to investigate the effect of steamed garlic powder (SGP) on the quality characteristics of Jochung, saccharide by barley melt. Physicochemical properties and sensory quality were determined in Jochungs were prepared that 5% (SGP 5), 10% (SGP 10), 20% (SGP 20) and 30% (SGP 30) of SGP to sikhe for making jochung and hard boiled (W/W). Turbidity and viscosity of SGP added groups increased than control, significantly. The viscosity was $133{\pm}10^3$ cps in control group, it higher than SGP added groups ($140{\pm}11^3{\sim}272{\pm}2^3$ cps). The pH decreased with increasing SGP concentration. Reducing sugar was significantly higher in SGP added groups than control group, especially 30% SGP addition group in $44.66{\pm}0.26$ mg/100 g. HMF (Hydroxymethyl-furfural) content increased with increasing of SGP concentration, and 30% SGP addition group was higher in 48% than control group. In HPLC determination, free sugars content increased with amounts of SGP addition level. Fructose and glucose contents increased while maltose and raffinose contents decreased. Fructose content was $0.84{\pm}0.02$ mg/100g in control group but $1.36{\pm}0.03{\sim}1.62{\pm}0.01$ mg/100 g in SGP added groups. In the sensory evaluation, the color of Jochung decreased dose dependently with the SGP. Garlic flavor was significantly greater in SGP added groups compared to that of control group. The overall acceptability had not significantly difference among control, SGP 5 and 10 group. Preference was decreased in contain more than 20% of SGP added groups. The optimal concentration of SGP was found in the range of less than 10%.

• Applied Biological Chemistry
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• 제24권3호
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• pp.200-205
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• 1981

Some chemical components, absorbance at 450nm and color of traditional and improved soysauce during fermentation were investigated. The traditional soysauce was made from soybean Meju and the improved soysauces were prepared from Kojis of various mixtures of soybean and wheat. The contents of reducing sugar were higher in the improved soysauces than in the traditional soysauce and it increased with proportion to the mixing amount of wheat. The contents of total nitrogen and amino nitrogen were increased gradually during fermentation and, in the improved soysauce, it increased with the amount of soybean. The changes of the absorbance and the chromaticity were greaser in the traditional soysauce than in the improved soysauce during fermentation. The increase of absorbance and the chromaticity was greater in the improved soysauce than that of the traditional soysauce during heating process. In the improved soysauce, the greater the amounts of wheat in Koji, the greater the increase of color.

• Applied Biological Chemistry
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• 제30권2호
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• pp.147-152
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• 1987

Soy sauce which was prepared with a mixture of defatted soybeans ant wheat flour koji added into acid-hydrolyzed soy sauce was evaluated for the chemical changes in levulinic acid, ethanol and amino acids composition during fermentation, Results showed that the highest reducing sugar content of $12.13{\sim}15.76%$ was found after $20{\sim}40\;days$ fermentation. The contents of total nitrogen, amino nitrogen, and ethanol increased with increase in fermentation time. A high levulinic acid content was fount at the initial fermentation period which was gradually decreased with further fermentation. The content of lactic acid also increased during fermentation. Amino acids such as Glu, Leu, Ala, Phe, Asp, Thr, Ser, Gly, Met, Tyr, Lys, His, Arg and Pro were detected in all tested groups. Higher values were found particularly for Glu, Leu, Ala and Phe and lower values for His, Tyr and Met. The most of amino acids increased in their contents after 120 days of fermentation.

• Food Science and Preservation
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• 제19권2호
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• pp.263-270
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• 2012

The chemical components and anti-oxidant activities of black currant were investigated. The pH, soluble solid and total acidity values were 3.36, 15.11 $^{\circ}Brix$, and 1.65%, respectively. The Hunter L, a, and b values were 18.20, 5.13, and 1.08, respectively. The proximate compositions were as follows; moisture, 77.64%; nitrogen free extract, 17.41%; crude fiber, 3.08%; crude protein, 1.28%; crude ash, 0.31%; and crude lipid, 0.28%, respectively. The mineral elements were K (177.36 mg/100 g), P (54.74 mg/100 g), and Ca (26.45 mg/100 g). The free sugar components were glucose (7.71%) and fructose (5.88%). The amino acid contents of the black currant were very rich in glutamic acid (105.73 mg/100 g) and deficient in cystine (5.29 mg/100 g). The ascorbic acid and total phenolic contents were 112.19 mg/100 g and 34.48 mg GAE/g, respectively. The ABTS and DPPH radical scavenging activity levels were 99.48% and 89.03% at the 10 and 1.25 mg/mL concentrations. The reducing power and FRAP of the black currant were dose-dependent. Thus, black currant can be an effective source of functional food substances, i.e., natural anti-oxidants.

• Food Science and Preservation
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• 제24권5호
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• pp.714-724
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• 2017

Soju is a Korean traditional distilled alcoholic beverage produced from mashes various crops and Nuruk which is cultured with wild microorganisms. This study was conducted to investigate rice-Soju brewing characteristics of yeasts isolated from Korean traditional Nuruk. The general components of rice (Hanarumbyeo) raw materials were 14.7 g of water, 6.8 g of crude protein, 0.9 g of crude lipid, 0.4 g of crude ash, and 76.5 g of carbohydrate in 100 g. Saccharifying and proteolytic activities in Hanarumbyeo ipguk (solid-state culture of Aspergillus luchuensis) were also determined. The alcohol content of the fermented wash from isolates was 15.37-16.58% (v/v), which is 16.7-36.0% higher than that of industrial yeasts (12.33-13.19%). Reducing sugar contents were 2.04-3.92 and 7.92-8.78 g/100 mL in the isolates and industrial yeasts, respectively. The isolated yeasts showed 25.2-52.7% higher yield of distillates (41% alcohol) compared to industrial yeasts. Forty-one components were detected in the rice distillated Soju (25% alcohol) and principal component analysis revealed differences between the isolated and industrial yeasts with respect to the contents of i-BuOH, isobutanal diethyl acetal, ethyl caprate, and tetradecanoic acid.

• Korean journal of food and cookery science
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• 제33권2호
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• pp.162-173
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• 2017

Purpose: The purpose of this study was to evaluate the folate contents and quality characteristics of commercial and fermented Kimchi and compare the correlation between folic acid and quality characteristics. Methods: The contents of total folate and quality characteristics were evaluated in 10 kinds of industrial and local Kimchi and nine kinds of other commonly consumed Kimchi. Changes in folate content and quality characteristics of Kimchi during 14 days of fermentation at $15^{\circ}C$ were compared. Results: Chungnam (L4) Kimchi had the lowest pH of 4.62, and acidity (0.57%) and salinity (3.26%) were highest compared to other areas. The content of total folate of D company (A) was the highest at $73.66{\mu}g/100g$. The content of total folate was significantly higher than those of Sesame leaf Kimchi (O9) and Young leafy radish Kimchi (O5) containing 65.77 and $62.82{\mu}g/100g$, respectively. The pH of fermented Kimchi decreased from 6.09 to 4.11 (p<0.05), and the acidity significantly increased (p<0.001) to 0.32-0.66%. Reducing sugar content decreased rapidly by 4 days and then slowly decreased (p<0.001). Total bacteria and lactic acid bacteria counts significantly increased (p<0.05) with fermentation period. Content of total folate was highest at $69.82{\mu}g/100g$ and $68.16{\mu}g/100g$ on days 0 and 2 of fermentation, after which it decreased to 77.6% at $15.61{\mu}g/100g$ on day 10 of fermentation. Conclusion: As a result, there was no definite trend regarding folate content in commercial Kimchi and other Kimchi. Young leafy radish, Chives, and Welsh onion Kimchi, which are rich in green leaves, are excellent folate source foods. The highest folate content of fermented Kimchi was identified on day 2 of fermentation. Therefore, it is recommended to use raw or immature Kimchi when using Kimchi as a folate source food.

• Journal of the Korean Society of Food Science and Nutrition
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• 제35권8호
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• pp.1070-1075
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• 2006

Food materials for kimchi manufacturing were treated by ozone or gamma irradiation to reduce the number of contaminated microorganisms before the manufacturing of kimchi. Counts of total aerobic bacteria, yeast and mold were $10^6{\sim}10^7 and 10^3{\sim}10^4\;CFU/g$ in the food materials, respectively. After treatment with ozone $(3{\sim}6\;ppm), the total aerobic bacteria were reduced to 1 log cycle or more, in a dose-dependent manner. In comparison, gamma irradiation was superior to ozone treatment. Especially, irradiation of 5 kGy fully eliminated the yeast and mold attached in the food materials for kimchi manufacturing. The contents of ascorbic acid and total and reducing sugar were not affected by ozone or gamma irradiation. Taken together, it is suggested that microorganisms contaminated on materials for kimchi manufacturing could be substantially reduced by ozone (up to 6 ppm) and gamma irradiation (up to 5 kGy), without effect on the nutritional contents.

• Journal of the Korean Society of Food Science and Nutrition
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• 제40권9호
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• pp.1314-1320
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• 2011

Vacuum drying was conducted for a steamed pumpkin-sweet potato slab to improve its quality, convenience and preference as snack. Steamed sweet potato was dried from 30 to $60^{\circ}C$ for 12 hr, after which moisture contents, colors, and taste were evaluated. The lowest moisture content was 0.22% upon vacuum drying at $60^{\circ}C$ for 12 hr. Lightness decreased while other color values (a, b and ${\Delta}E$) increased with increasing drying temperature and drying time. Reducing sugar and soluble solid contents ranged from 98.7~268.11 mg/g and $19{\sim}72^{\circ}Brix$, respectively. Sensory score of the sample was the highest when dried at $50^{\circ}C$ for 6 hr. The optimum drying conditions were predicted to be $48.5{\sim}62^{\circ}C$ and 5.1~7.1 hr by response surface methodology.