• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.681-686
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• 2005

The purpose of this study was to analyze the chemical component of Camellia japonica L. according to picking time. Leaves of Camellia japonica L. were picked in April and May,2003. Free sugars (fructose, glucose and sucrose) and organic acids (citric acid, tartaric acid, succinic acid, acetic acid) were present in the Camellia japonica L. leaf. The contents of total free sugars and organic acids increased as picking time was delayed. The major components of free amino acids were aspartic acid, glutamic acid and histidine, and those of total amino acids were histidine and alanine. The contents of total free amino acids and total amino acids were decreased as picking time was delayed, while the ratio of essential amino acids to the total amino acids increased. The amount of minerals (P, Ca, K, Na and Fe), chlorophyll and total polyphenol increased as picking time was delayed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.586-591
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• 1993

The compositions of amino acid in the protein and fatty acid in the lipid of Lespedeza x chiisanensis T. LEE were analyzed by HPLC and GC, respectively. The contents of crude oil and protein from the extracts were 11.13% and 5.18%, respectively. The amount of free anino acids in the protein was 443.14mg/100g, and 94.84mg/100g of essential amino acid were contained in the free amino acid. The amount of total amino acids in the protein was 3159.85mg/100g, and 1068.18mg/100g of essential amino acid were contained in the total amino acid. The compositions of fatty acid in the lipid were $C_{18\;:\;2}=45.05%,\;C_{18\;:\;3}=18.71%,\;C_{19}=14.70%,C_{18\;:\;1}=6.81%,\;C_{16}=4.35%,\;C_{16\;:\;1}=1.59%$ in order, respectively. 72.44% of unsaturated fatty acids were contained in the lipid.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.418-421
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• 2006

Fatty acid methyl esters, also referred to as biodiesel, have been determined to have a great deal of potential as substitutes for petro-diesel. In order to enhance productivity in the biodiesel production process, feedstocks were previously recommended to be anhydrous, with a free fatty acid content of less than 0.5%. In this study, the effects of several catalysts, methanol molar ratio, catalyst amount, and reaction time on the reduction of free fatty acid level were studied with a simulated feedstock consisting of 20% oleic acid in rapeseed oil. Ferric sulfate was selected as the best catalyst. Increasing the catalyst amount and methanol molar ratio is very effective in decreasing the acid value of the simulated mixture. Our results may provide useful information with regard to the development of more economic and efficient free fatty acid removal system.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.389-392
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• 1994

Changes in free amino acids and amino nitrogen of traditional kochujang were investigated during 180 days of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley, and Sachun kochujang prepared with wheat. Amino acids remarkably increased during fermentation were methionine, glutamic acid, isoleucine, leucine and tyrosine. However, regardless of kinds of kochujang major free amino acids were serine, aspartic acid, glutamic acid and proline. Glutamic acid was noted as the most contributing to the savory taste of kochujang in relation to the increasing ratio and content among tree amino acids during fermentaion. The correlation coefficent between totals of free amino acids and the contents of amino nitrogen were relatively high (0.87

• Korean journal of food and cookery science
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• v.10 no.3
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• pp.225-231
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• 1994

This study was intended to observe the effect of cooked glutinous rice flour and soused shrimp on the fermentation of Kimchi samples were fermented for 11 days at 10$^{\circ}C$ after they were previously fermented for 6 hours at 20$^{\circ}C$. Changes of pH, total acidity, salt content, reducing sugar content, free amino acid content, total vitamin C content, and ascorbic acid content were measured. The results were as follows; 1. Soused shrimp and glutinous rice flour added in Kimchi acted as lactobacilli growth enhancer during fermentation. 2. Initial cincentrations of redng sugars in Kimch samples with no soused shrimp, 5% and 10% sosed shrimp were 7.5~8.3 mg/g, 3.0~4.7 mg/g and 0.5~0.6 mg/g respectively. Kinchi samples with glutinous rice flour showed higher reducing sugar contents than Kimchi samples without it. 3. Free amino acid contents in Kimchi samples gradually decreased during fermentation at 10$^{\circ}C$. According to their soused shrimp concentration, contents of free amino acid of Kimchi samples were significantly different. And Kimchi samples with glutinous rice flour showed lower free amino acid contents than Kimchi samples without it. 4. Total vitamin C contentrations of Kimchi samples were 24.5~28.0 mg% at the initial stage of fermentation and 15.0~19.2 mg% at the final stage of fermentation. During the fermentation of Kimchi, the higher soused shrimp concentration, the less total vitamin C contents were remained. 5. During the fermentation, ascorbic acid contents of Kimchi samples were not affected by soused shrimp and glutinous rice flour.

• Applied Biological Chemistry
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• v.41 no.3
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• pp.234-239
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• 1998

In non-destructive evaluation of free acid content in apples by near- infrared spectroscopy(NIRS), browning and heat treatment of squeezed apple juice affected to the accuracy but titrable alkali concentration did not. The free acid content in apples after harvest was able to determine using different apples in harvest time for calibration making. The result of MLR, multiple correlation coefficient(R) was 0.77 and standard error of prediction(SEP) was 0.03%. The free acid content in apples during storage was able to determine using calibration equation established with stored apples, R was 0.90 and SEP was ca. 0.04%. The prediction accuracy by LAIR was not sufficient for use of quantitative analysis of free acid content in apple, but classification of law and high level in acid content was supposed to be applicable.

• Applied Biological Chemistry
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• v.38 no.4
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• pp.345-352
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• 1995

The influence of vacuum cooling and modified atmospheric packaging was investigated about browning degree, polyphenoloxidase(PPO) activity and free amino acid of shiitake mushroom. During storage, surface browning was inhibited by precooling. PPO activities of shiitake mushroom was increased during storage. Especially, PPO activity was rapidly increased as surface browning was proceeded. And PVC-wrapped mushroom was lower than carton box-packed mushroom in the changes of surface browning and PPO activity. Total free amino acid contents of shiitake mushroom was 2,510 mg% at harvest, but free amino acid content of shiitake mushroom decreased consistantly during storage. Precooled mushroom had more free amino acid content than non-precooled and their contents were fluctuated by storage temperature, packaging methods and storage periods.

• Journal of Nutrition and Health
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• v.35 no.10
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• pp.1031-1037
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• 2002

The purpose of present study was to evaluate the effect of endurance exercise training on skeletal muscle free amino acid concentrations, and differences in free amino acid concentration between soleus muscle which consists of mostly slow twitch oxidative fiber and extensor digitorum longus muscle which consists of fast twitch oxidative glycolytic fiber. Sixteen male SD rats (4 weeks old) were randomly devided into two groups, and fed a purified AIN-93M diet with or without aerobic exercise training according to the protocol (running on the treadmill at 25 m/min for 60 min, 5 days a week) for 6 weeks. Exercise-training for 6 weeks significanly reduced the commulative body weight gain (p＜0.05) and food efficiency ratio (p＜0.01) of rats. The result showing mitochondrial citrate synthase activity of soleus muscle was significantly higher in exercise-trained rats compared to the value for control animals (p＜0.01) indicates aerobic exercise-training was successfully accomplished in the trained group. No difference was found in the muscle aminogram pattern between soleus muscle and extensor digitorum longus muscle of control animals. However, free amino acid concentrations of soleus muscle were from 1.2 to 3.9 times of those found in extensor digitorum longus muscle of control rats, depending on an individual amino acid. Intermediate level of endurance exercise training for 6 weeks did not influence concentrations of most of free amino acid in soleus muscle of rats collected at an overnight fasted and rested state. In contrast, isolucine and leucine concentrations in extensor digitorum longus muscle of exercise-trained rats were significantly lower than those for control animals. These results indicate that aerobic energy metabolism had not been efficiently conducted, and thereby the utilization of BCAA for energy substrate was enhanced in fast twitch oxidative glycolytic fibers of extensor digitorum longus muscle of rats followed exercise-training protocol for 6 weeks.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.256-263
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• 2001

Physicochemical characteristics of kochujang prepared with meju, koji and mixture of meju and koji were analyzed during fermentation in order to improve quality of traditional sikhe kochujang. Amino nitrogen content, an index of kochujang quality, was remarkably higher in kochujang prepared with p-2 koji, p-1 koji, mixture of p-2 koji and meju. Titratible acidity of kochujang slightly increased and pH of kochujang increased until 40 days of fermentation and then decreased there after. Citric acid was found as a major organic acid followed in decreasing order by malic, oxalic, succinic, acetic and lactic acids. As a free sugar, maltose, glucose and fructose were detected. Free sugar content was higher in kochujang prepared with p-1 koji than the others. The major free amino acids were aspartic acid, glutamic acid, alanine, phenylalanine and arginine, and total free amino acid content was higher in kochujang prepared with koji, and mixture of meju and koji than the one with traditional meju only. In sensory evaluation, all tested groups did not show a significant difference. This result indicates that addition of koji to sikhe kochujang influences on taste components like free sugars and free amino acids, but decisively not on the sensory properties.

• The Korean Journal of Food And Nutrition
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• v.13 no.1
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• pp.6-12
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• 2000

This study was performed to investigate the changes in chemical composition of Panax ginseng leaf by harvesting at July, August and September. The levels of crude protein of dried ginseng leaf were decreased from 17.12mg% to 14.26% by harvesting month, however, crude fat contents of dried ginseng leaf were increased slightly from 1.90% to 2.49%. Three kinds of free sugar, i.e. glucose, fructose and sucrose were found in dried ginseng leaf and maltose was not found. Free sugar contents were increased by delaying harvest, but free amino acid were decreased. Total free amino acid was decreased in delayed harvesting month, serine was revealed superior in free amino acid composition, and valine was revealed next order. In minerals, contents of Ca were from 1,306.1mg% to 1,923mg%, that of K were higher than others patricualy as 1,266.9∼1,216.0mg%. The contents of minerals were existence in order of Mg, P, Na, Fe, Mn, Zn and Cu, abundantly. Total vitamin C were present of 391.0∼336.1mg%, and the contents were decreased as delayed as harvesting period despite of the plentiful content. In fatty acid composition of ginseng leaf, the palmitic acid content was as 40% higher than other fatty acids, remarkably.