• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.5
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• pp.827-832
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• 1998

Soybeans(Hwangkeum Kong) were stored at 5$^{\circ}C$, $25^{\circ}C$ and 35$^{\circ}C$ for 8 months to investigate the changes of the physicochemical properties. Less physicochemical changes were detected in the soybeans stored at 5$^{\circ}C$ than those stored at $25^{\circ}C$ and 35$^{\circ}C$. High temperature and long term storage caused a decrease in the nitrogen solubility index, whereas increases in acid value and organic acid content were detected. As the storage period was extended at high temperatues, the content of unsaturated fatty acids decreased, but the content of saturated fatty acids increased. Decoloration of soybeans was clearly recognized under high temperatures. The water soluble compoents such as total solids, nitrogen and reducing sugar during water-soaking at 2$0^{\circ}C$ for 16hrs were appreciably eluted from the soybeans stored for 8 months at high temperatures. The pH of the water extract slightly shifted to the acidic range.

• Food Science and Preservation
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• v.16 no.6
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• pp.893-899
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• 2009

We compared the physicochemical properties of commercial brown rice vinegar fermented with and without ethanol. The pH and total acidity did not significantly differ between the two types of vinegar. Sugar content, reducing sugar content, and free sugar concentration were higher in commercial brown rice vinegar fermented with ethanol, whereas browning, turbidity, and overall color darkness were higher in vinegar fermented without ethanol. The ratio of acetic acid to total organic acids was 0.94 - 0.96 and 0.97 - 1.00 in commercial brown rice vinegar fermented with or without ethanol, respectively. A higher content of total amino acids, 93.07 - 509.48 ppm, was found in vinegar fermented without ethanol. Fermentation conditions affected the physicochemical properties of brown rice vinegar, as shown by significantly higher $\gamma$-aminobutyric acid (GABA) content in brown rice vinegar fermented without versus with ethanol.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.272-277
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• 1993

Chemical composition was determined to evaluate the quality of traditional Ewhaju during brewing. The content of moisture, total sugar, reducing sugar, crude protein and crude ash of Ewhaju after the lapse of 20 days from brewing were 47.01%, 47.57%, 29.45%, 4.81% and 0.09%, respectively and free sugar composed with 28.07% of glucose and 1.30% of maltose compared with 17.43% of glucose in one year aged Ewhaju. Contents of minerals were Ca 4.8mg%, Mg 9.2mg%, K 33.0mg%, Na 16.0mg%, Mn 0.76 ppm, Fe 35.0 ppm, Zn 1.1 ppm, Cu 0.12 ppm, Cr 0.20 ppm and Pb 0.22 ppm and rarely changed during fermentation. Total amino acids were 4.23% immediately after brewing 4.54% after the lapse of 100 days. In change of amino acids, methionine and tyrosine slightly increased during fermentation. Total acid contents of Ewhaju at immediately after brewing, in the lapse of 100 days and aged one year were 0.25%, 2.16%, 3.70%, respectively and 0.05%, 0.72% and 1.04%, in volatile acid. The pH in Swhaju remarkably decreased during fermentation; 6.1 at immediatly after brewing, about 3.9 at 100 days and 365 days fermentation.

• Applied Biological Chemistry
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• v.43 no.4
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• pp.277-284
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• 2000

In order to investigate the changes of microorganisms, enzyme activity and physiological functionality of five types of traditional Deonjang prepared with various concentrations of Lentinus edodes. The pH of traditional Deonjang was decreased but total acidity was increased during fermentation. NaCl concentrations was increased up to $15.67{\sim}16.02%$ until $30{\sim}45$ days of fermentation but decreased after that. Amino acidity was increased on the traditional Deonjang with increasing the mixture ratio of Lentinus edodes. Reducing sugar content was increased up to $30{\sim}45$ days of fermentation. Total sugar content was increased up to $18.21{\sim}20.57%$ until 30 days of fermentation. As the mixing ratio of Lentinus edodes increased, total sugar also increased. The number of bacteria was highest in all sample after 45 days fermentation, while that of mold was decreased during fermentation. Amylase activity was decreased but protease activity, tyrosinase inhibitor and ACE inhibitor were increased on the traditional Doenjang with increasing the mixture ratio of Lentinus edodes. Antimutagenic activities of traditional Deonjang (10% Cortinellus edodes) were 83.15%, 65.88% against MNNG, NPD on S. typhimutium TA100 and 54.59%, 55.00% against NQO, NPD on S. typhimutium TA98

• Korean Journal of Plant Resources
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• v.9 no.3
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• pp.211-217
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• 1996

As a part of studies on the development of a Gugisuen(Lycium chinense M.), which is one of the unutilization of waste resources, we investigated the composition of fatty acid and amino acid according as picking period and varieties of Gugisuen. The chemical components of Gugisuen were as follows : 1. Proximate composition of Gugisuen were Cheongyang native had the highest contents of crude lipid, crude protein, total sugar, and the contents of crude protein, total sugar, and reducing sugar was the highest picked on June 20. 2. The contents of $P_2O_5$, $K_2O$, CaO, MgO, Cu, and Mn were higher in Cheongyang native than that of other varieties. And mineral contents of Gugisuen picked on May 10 were the highest. 3. The major fatty acids were linoleic, linolenic acids, and these unsaturated fatty acids composed about 50% of total fatty acids. Fatty acid compositions between each varieties were not significant, and those components were the highest in Gugisuen picked on May 10. 4. Eighteen amino acids were identified from Gugisuen, glutamic acid, the highest content was $10.05\sim10.94%$ and these contents increased in the order to aspartic acid > glycine > alanine > leucine > lysine. The contents of serine, arginine, methionine, cystine-2 and isoleucine were higher in late harvest time and glutamic acid and tryptophane were higher in early harvest time.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.989-996
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• 2008

In this study we assessed the effects of gamma irradiation ($0.5{\sim}3\;kGy$) on the microbial and physico-chemical characteristics of maesil (Prunus mume) stored for 9 days at $20^{\circ}C$. Total aerobic bacteria, yeasts and molds were significantly decreased with increases in the irradiation dosage. In terms of the Hunter's color value, irradiated samples evidenced a higher b-value, but a lower a-value than the non-irradiated samples. Hardness was reduced with increment in the irradiation dose level. The contents of total sugar, hydrogen donating activity and organic acids were not affected by irradiation. The reducing sugar contents of the irradiated samples were superior to those of the non-irradiated samples. Vitamin C contents were reduced with the progression of storage periods and increases in the dosage level. These results demonstrated that gamma irradiation of 0.5 to 3 kGy affected the microbiological safety of maesil, but did not affect the physico-chemical characteristics(total sugar, hydrogen donating activity and organic acid) but the Hunter's color value, hardness, and vitamin C contents of the maesil deteriorated with gamma irradiation.

• Food Science and Preservation
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• v.11 no.4
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• pp.516-521
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• 2004

The study was intended to develop a yam snack to increase the consumption and the added value of the yam which has many kinds of medicinal effects and functions. Moisture content of a freeze-drying yam snack was higher than those of hot wind drying and vacuum drying yam snack. However, carbohydrate content was opposed to it. The content of soluble proteins in freeze drying yam snack was 6.43 mg/100g, and lower than that those in hot wind drying and vacuum drying yam snack. The contents of total sugar and reducing sugar were not noticeably different by processing methods. The major organic acids of yam snack were malic, acetic, acids, and acetic acid. Citric acid were rich contented in hot wind and vacuum dried yam snack, but the content of malic acid in freeze dried yam snack was higher than those in hot wind and vacuum dried yam snack. The contents of the amino acids and total amino acids showed the highest contents in vacuum dried snack and the next came in hot wind dried snack and freeze dried snack order. The content of free amino acids were not different by processing methods. Total content of vitamin C were not different by processing methods, but a ascorbic acid was higher in freeze dried yam snack than those in other. The dehydroascorbic acid contents of the hot-air and vacuum dried snack was higher than those of the freeze dried snack, Potassium, sodium and magnesium were the main minerals of the yam snacks.

• Food Science and Preservation
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• v.20 no.3
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• pp.330-335
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• 2013

This study was conducted to investigate the food value of Cudrania tricuspidata at its various maturation stages. The pH, total acid and reducing sugar contents of its fruit juice were determined to have been 4.2~5.1, 1.4~2.0% and 5.4~8.6%, respectively. The general chemical components of its fruit were observed as 76~80% moisture, 2.2~3.5% crude protein, 1.7~2.9% crude fat, 0.8~1.2% ash and 14.5~16.4% carbohydrate. Its free sugar, glucose and fructose contents were determined. The fructose contents of both its ripened and over-ripened fruits were higher than their glucose contents. Organic acids such as oxalic acid, citric acid, tartaric acid, malic acid and succinic acid were detected, and the concentration of the malic acid and the succinic acid were found to have been most abundant. The K content was higher than the amounts of other minerals, such as Ca, Fe, K, Mg, Na and P. Its vitamin C and the total amount of its dietary fiber were 127.5~149.2 mg% and 22.7~38.7%, respectively. Its insoluble dietary fiber content was higher than its soluble dietary fiber content. Its total polyphenol and flavonoid content were 18.9~19.6 mg% and 40.9~48.2 mg%, respectively.

• The Korean Journal of Food And Nutrition
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• v.32 no.3
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• pp.226-235
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• 2019

In this study, the product characteristics and physicochemical properties were investigated through collection of commercial porridge. The addition rate of grain raw materials was about 6.5~11.75%, glutinous rice was added at a rate of about 23~60% to improve the viscosity and various other food additives were used. The moisture content characteristics varied among the products. The rotational viscosity of CP (Commercial Porridge)4 was the highest at 39,054 cP, while the flow viscosity of CP3 was least at 4.80 cm/30 seconds. The starch content differed among the products in the range of total starch 6.96~8.08%, amylose 1.41~2.61%, total sugar 6.55~12.81% and reducing sugar 0.50~0.99%. Particularly, total sugar showed a very high correlation (-0.920) while rotational viscosity and color value (b) showed significant correlation with most of the properties i.e. moisture, solids content etc. There was a rapid increase in the reactivity of starch degrading enzyme at the early stage of the reaction which gradually decreased with time. The physicochemical characteristics of commercial porridge presented in this study could be expected to increase the industrial use value of the related research because it considers the quality of the currently commercialized porridge for the future selection of suitable porridge raw materials.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.75-81
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• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.