• Korean Journal of Food Science and Technology
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• v.5 no.4
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• pp.258-267
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• 1973

Chemical analysis and enzymatic hydrolysis of certain Korean acorns were performed in order to make use of the local acorns. Exclusion of tannin from acorns is aided in the processing. Studies of these were undertaken and the results obtained are summarized as follows; 1. Several Korean acorns were used to analyze their proximate composition, tannin and major inorganic principles. The content of acorn tannin was found to be 6.5 to 7.5%. 2. An Attempt was made to screen suitable strains in order to make acorn-tannin-hydrolyzing enzyme accumulated in the culture broth, and Aspergillus flavus and Asp. sp. AN-11, which showed in their culture broths, were obtained from the contaminated acorns. 3. Cultural measures for the strains of Aspergillus flavus and Asp. sp. AN-11 for an improved tannase production and optimal conditions were determined.

• Applied Biological Chemistry
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• v.38 no.2
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• pp.147-150
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• 1995

Effects of gelation conditions on physical properties of dover sole skin gelatin prepared by fractional precipitation with ethanol were investigated. The physical properties such as gel strength, melting point and gelling point of both ethanol treated and non-ethanoltreated gelatins were improved as concentration of gelatin was increased. The physical property of 10% ethanol treated gelatin sol reached maximum at pH 6.0, whereas non-treated one showed maximum at pH 5.0. Both ethanol treated and non-treated gelatin gel showed the higher gel strength and melting point at lower temperatures and longer period of time. Generally, the physical properties of ethanol treated gelatin gel was better than those of non-ethanol treated gel.

• The Korean Journal of Food And Nutrition
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• v.28 no.6
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• pp.1019-1025
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• 2015

The influence of aging on the flavor precursors and volatile compounds of top round beef was studied. The concentrations of free amino acids, nucleotides, creatine, dipeptides, and volatile compounds were measured after top round from Hanwoo was aged at $4^{\circ}C$ for 21 days. The amount of free amino acids in top round significantly increased with the increase of aging period. There was no effect of aging on the concentrations of adenosine monophosphate or inosine in top round. The inosine monophosphate content of top round significantly decreased with age, while the hypoxanthine content increased. The concentrations of creatine, carnosine, and anserine in top round were not influenced by aging. In total, 24 volatile compound were identified in aged, cooked top round. Of these, the quantities of aldehydes (propanal, pentanal, hexanal, heptanal, octanal, and nonanal), hydrocarbons (pentane and octane), 2-butanone, ethyl acetate, and pyridines (4-ethynyl-pyridine and 4-acetyl-pyridine) significantly increased after aging. We conclude that the flavor of top round can be improved by aging.

• The Korean Journal of Food And Nutrition
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• v.27 no.3
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• pp.495-506
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• 2014

This study was conducted to measure the effect of a community-based nutritional intervention program on dietary behaviors and nutrient intakes of low-income elderly women in Korea. The subject of the study was a group of 88 elderly women using the free meal service in Dong-gu, Gwangju city in Korea. The study was carried out from April to July 2009, and the pretest, application of nutrition education, and post-test were applied in each stage. This community-based nutrition intervention program consisted of snack supplement and nutrition education provided three times a week and 36 times in total. The nutrition education was led by the nutritionists and professionals using various educational media. Snack supplement included were milk, soymilk, carrot juice, bread, yogurt, and bananas. The result of pretest showed that the nutrient intakes of the subjects were much below the Recommended Nutrient Intake (RNI) level of Dietary Reference Intake for Koreans. Comparison of the dietary behavior score and nutrient intakes before and after the nutritional intervention program indicated that the food behavior score increased from 3.1 to 5.6 (P<0.001) and intake of energy, protein, carbohydrate, thiamin, niacin, vitamin C, iron, and potassium of the subjects all increased significantly (P<0.05). Mean Adequacy Ratio (MAR) of their nutrient intakes was also improved from 0.53 to 0.64 (P<0.01). These results indicated that the nutrition intervention program conducted in this study was effective in improving dietary behavior and nutrient intakes of elderly women in local community.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.272-277
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• 2018

This research was conducted to elucidate the optimum conditions for the antibacterial activity of konjak jelly using the evolutionary operation-factorial design technique. In the first set of experiments, concentration of a coagulation agent, soaking liquid, and temperature of water were set to 0.4%, $0.6{\times}10^{-2}N$, and $65^{\circ}C$ as a central point, respectively. The highest antibacterial activity was acquired at E21, in which the number of bacteria was 1.25 log cfu/g. Because the code of changes in the main effect was (-), it could be decided that the central point of the first set was not the optimum point. Although antibacterial activity in the second set was improved, the values of the main effect were higher than that of changes in the mean effect. The central point of third set was concentration of coagulation agent 0.8%, concentration of soaking liquid $1.0{\times}10^{-2}N$, and temperature of water $65^{\circ}C$. It was found that the antibacterial activity of central point in the third set was highest among all the tested set. Further, all the necessary conditions were appropriate to reach the optimum condition. The antibacterial activity of the central point in third set was more than 1,000 times higher than that of E11, in first set.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.8
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• pp.1291-1300
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• 2018

Objective: This experiment was conducted to investigate the effects of dietary crude protein (CP) level and exogenous protease supplementation on growth performance, serum metabolites, carcass traits, small intestinal morphology and endogenous protease activity in broiler chickens reared under a tropical climate. Methods: A total of 480 day-old male broiler chicks were randomly assigned to eight dietary treatments in a $4{\times}2$ factorial arrangement. The main effects were CP level (21.0%, 19.7%, 18.5%, or 17.2% from 1 to 21 days and 19.0%, 17.9%, 16.7%, or 15.6% from 22 to 35 days) and protease enzyme supplementation (0 ppm or 500 ppm). All experimental diets were fortified with synthetic feed-grade lysine, methionine, threonine and tryptophan to provide the minimum amino acid recommended levels for Cobb 500. Results: Reducing dietary CP linearly reduced (p<0.05) growth performance, serum albumin, total protein, and carcass traits and increased (p<0.05) serum triglycerides and abdominal fat. There was no consistent effect of reducing dietary CP on morphological parameters of the intestine and on the pancreatic and intestinal endogenous protease activity (p>0.05). Protease supplementation improved (p<0.05) feed conversion ratio, body weight gain, carcass yield and intestinal absorptive surface area. Conclusion: Protease supplementation, as measured by growth performance, intestinal morphology and carcass yield, may alleviate the detrimental effects of low protein diets in broiler chickens.

• Korean journal of food and cookery science
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• v.31 no.6
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• pp.781-790
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• 2015

Germinated brown rice (GBR) flour (0%, 25%, 50%, 75% and 100%) was added to brown rice (BR) and white rice (WR) flours and the densities of pound cake batters, morphology, color value, textural properties, sensory preference test, and hardness during storage were investigated, in order to develop health functional gluten-free rice pound cakes with high nutritional value. The rice was milled with the newly developed rice milling method. The entire shape and cross section of all cakes were symmetrical and desirable. The density of pound cake batter and weight of cake increased with addition of increasing GBR. Specific volume was not significantly different (2.1-2.4 mL/g). Textural properties of cakes between WR-GBR and BR-GBR showed different trends with adding GBR. On the sensory test, overall quality of rice pound cake did not significantly differ between rice flour types. Hardness of rice pound cakes and brittleness decreased with increasing addition of GBR flour. The hardness and the peak intensity at $2{\theta}=17^{\circ}$ decreased with increasing addition of GBR. The results, that addition of GBR flour improved the nutrition value and functionality of gluten free rice pound cakes and prevented staling of rice pound cakes during storage.

• Korean journal of food and cookery science
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• v.33 no.1
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• pp.94-103
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• 2017

Purpose: This study developed sourdough bread according to consumers' preferencesby shortening the sourdough fermentation process time through addition of makgeolli to sourdough. Methods: Fermentation time was measured by adding makgeolli and water to wheat flour. Results: Fermentation time was shorter than that of starter made with only water and flour, with 5 hours of primary fermentation and 3 hours of secondary fermentation. The optimum mixing ratio was 400 g of flour, 192 mL of water, and 48 mL of makgeolli. An increase in makgeolli sourdough content decreased crude protein and moisture contents of white bread. Crude fat and ash contents increased, and volume of bread was decreased as sourdough increased. The height of bread prepared with makgeolli sourdough was lower than that of bread without makgeolli sourdough. According to the results of the texture measurement, hardness, gumminess, and chewiness of sourdough group were lower as the addition of sourdough increased. Addition of makgeolli sourdough to white bread resulted in decreased lightness, but increased yellowness of white bread. Preparation of white bread with addition of sourdough improved taste and flavor compared to bread prepared only with wheat flour. Conclusion: The highest sensory preference was observed for white bread prepared whit 5 g of sourdough.

• Korean Journal of Food Science and Technology
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• v.27 no.3
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• pp.370-374
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• 1995

By exposing the complex enzyme solution to alkaline condition, it was possible to remove the protease activity selectively without inactivation of soybean cell wall degrading activity of the crude enzyme complex produced by Aspergillus niger CF-34. Optimum reaction conditions were as follow. pH was $9.0{\pm}0.1$, temperature was $20^{\circ}C$ and reaction time was 30 min with gentle stirring. Over 90% of protease activity could be eliminated while the activities of pectinase, polygalacturonase, xylanase, carboxymethyl cellulase and soybean cell wall degrading enzyme were maintained to $80{\sim}100%$. Through alkali treatment, it was discovered that the quality and organoleptic properties of soy protein produced by this enzymes were improved because the hydrolysis of protein and formation of bitter peptide were decreased.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.236-241
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• 1976

A barley (20-30%)-wheat (80-70%) flour gave generally acceptable noodle-making characteristics, in which naked barley flour showed somewhat better results than covered barley flour. And also for over 40% barley flour in the barley-wheat flour, the addition of xanthan gum improved the noodle-making characteristics. A naked barley-defatted soy flour could make dried noodles with only high NSI (Nitrogen Solubility Index) defatted soy flour, however this mixture was not considered to be feasible for noodle-making. In cooking characteristics of barley-wheat flour noodles, naked barley flour was more acceptable than covered barley flour and xanthan gum influenced the water absorption and volume expansion of noodles during cooking. The firmness, cohesiveness and gumminess in cooked noodles made of the barley-wheat flour increased and then decreased as the amounts of barley increased. The mixing of defatted soy flour (high NSI) to naked barley flour increased the firmness and gumminess of cooked noodles.