• Korean journal of food and cookery science
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• v.6 no.2
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• pp.51-58
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• 1990

Quality deterioration of barley drink during storage was examined by measuring viable count, titratable acidity (TA), turbidity and pH of barley drinks with or without barley particles stored at temperatures of 20, 25, 30, and 35$^{\circ}C$. Qualitative analysis of organic acids in spoiled barley drink was also performed. TA of barley drink during storage increased to 0.009, 0.0095, 0.0097 and 0.020% at 20, 25, 30 and 35$^{\circ}C$, respectively. TA reached the mixima between 7 and 10 days of storage and reduced from then on. pH values followed the exactly reverse trend of TA. The rate of bacterial spoilage of barley drinks was faster when it was stored at higher temperatures. The numbers of bacteria were in the range between 9.0${\times}10^6-8.0{\times}10^8$ cells/ml depending on the storage temperatures and the different brands. Those samples with higher bacterial growths showed higher optical densities. Volatile organic acids such as acetic, formic, propionic, isobutyric, isovaleric acids were detected in addition to ethyl alcohol. Non-volatile organic acids such as pyruvic, lactic, oxalacetic, succinic, fumaric acids were detected. Among them, acetic acids were most important in their quantities. Five different kinds of spoilage bacteria were isolated and identified as Bacillus Licheniformis, Bacillus coagulans, Badillus cirulans, Bacillus stearothermophilus and Bacillus brevis, all of which were found to form endospores.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.224-230
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• 2013

The objective of this study was to identify the content of phenolic and volatile organic compounds in edible and non-edible parts of 'Seolhyang' strawberry plants. We performed a comparative chemical analysis of the compounds found in roots, leaves, petioles, runners, and unripe and ripe fruits during vegetative propagation and reproductive growth. The contents of ellagic and gallic acids in the leaves of runner plants during vegetative propagation were $7.36{\pm}1.10$ and $5.07{\pm}3.66mg{\cdot}g^{-1}$ FW, respectively, and were higher than those in the other parts. The main volatile organic compound was identified as 3-hexen-1-ol, and it was mostly detected in leaves. The content of ellagic acid in leaves during reproductive growth was $12.96{\pm}2.30mg{\cdot}g^{-1}$ FW, while that in the other parts was below $6.00mg{\cdot}g^{-1}$ FW. The content of gallic acid in unripe fruits was $2.75{\pm}0.48mg{\cdot}g^{-1}$ FW and was higher than that in the other parts. Ripe fruits contained the lowest contents of ellagic and gallic acids but contained the most diverse volatile organic compounds, including sesquiterpenes, among the tested plant parts. The results indicate that non-edible parts (e.g., leaves and unripe fruits) of strawberry plants can be used as a raw material for antioxidant and anti-inflammatory agents, and edible parts (i.e., ripe fruits) can be available for making an essential oil.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.21 no.1
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• pp.57-66
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• 1988

As a method of utilization of sardine, the processing conditions of the sardine sauce extracts and the taste compounds of products were investigated. To prepare the sardine sauce extracts, chopped sardine was mixed with $1\%$, onion powder, $1\%$ garlic powder, $1\%$ red pepper powder, loft koji and $50\%$ water, and then hydrolyzed under different conditions of hydrolysis. The optimum conditions for hydrolysis were $55^{\circ}C$, 6 hours, pH 6.5-7.0. After hydrolysis, the hydrolysates were heated at $100^{\circ}C$ for 20 minutes with $5\%$ soybean protein isolate for inactivation of enzymes and improvement of bitter taste of the hydrolysates. Finally, $10\%$ salt was added to develop the characteristic taste of sauce extracts. The major taste compounds of the products were free amino acids, non-volatile organic acids and nucleotides and their related compounds. The major free amino acids in the products were arginine, histidine, lysine, glutamic acid, phenylalanine, leucine and alanine. The contents of these free amino acids were in the range of $68.2\%\;to\;69.9\%$ of the total free amino acids of products. The major non-volatile organic acids ill the products were lactic acid and $\alpha-ketoglutaric$ acid which occupied more than $95\%$ of total non-volatile organic acids. The contents of free amino acids, non-volatile organic acids and nucleotides and their related compounds were not changed during storage. Total creatinine, betaine and TMAO were seemed to act an auxiliary role in taste of the products. Judging from the results of chemical experiments and sensory evaluation, the product prepared with koji and soybean protein isolate was excellent as seasoning materials.

• The Korean Journal of Food And Nutrition
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• v.13 no.6
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• pp.529-533
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• 2000

The marsh calm soup was prepared with 2 volumes of boiling water and heated for 0, 5, 10, 30, 60 and 120 minutes. As the boiling time prolonged, water content decreased gradually, while protein content increased. Free amino acid content was the highest with 30 minutes of boiling showing 103.1 mg/100g, and decrease showly thereafter. Among the free amino acids, alanine was the most abundant followed by proline, glutamic acid and glycine. Degree of protein hydrolysis increased as boiling prolonged. In the non-volatile organic acids, succinic acid was the highest(137.08 mg/100g with 30 minutes of boiling), followed by oxalic acid, magic acid and lactic acid. The optimum boiling time for marsh calm soup was evaluated to be 30 minutes.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.184-191
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• 1995

This study was designed to investigate the changes In chemical characteristics of traditional kochujang increase in fermentation time, whereas that of total sugar decreased rather rapidly during aging of meju. Amino nitrogen content of meju Increased sharply up to 40 days of fermentation and then decreased there after On the other hand, ammoniacle nitrogen content continued to increase with increasing aging time. Initially, maltose was the most abundant free sugar, but was later replaced by glucose or fructose as the fermentation proceeded. Among non-volatile organic acids, pyroglutamic acid was present at an appreciably other organic acids did not change considerably during fermentation. The total free amino acid content Increased up to 40th day of aging and then decreased thereafter The was the most abundant amino acid followed in decreasing order by Try and Glu in meju fermented for 40 days.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.398-403
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• 1996

To produce low salt fermented anchovy by an accelerated method with Asp. oryzae and Bacillus sp. koji and taste properties after the 60 day fermentation were examined. The main free amino acids of 60 day fermented anchovy paste were valine, isoleucine, proline, alanine, lysine, glutamic acid and aspartic acid. Total amount of free amino acids was the highest in non koji anchovy paste wit 2,624.76mg%. Among the koji added samples, Asp. oryzae koji added on was the highest in the amount o free amino acids. Hypoxanthine accounted for 84.14~95.4% of total nucleotides and their related compounds; Asp. oryzae koji added anchovy paste was the highest in nucleotides other related. Citric acid and lactic acid accounted for 94.9~96.7% of total non-volatile organic acids; Asp. oryzae koji added sample was the highest in non-volatile organic acids with 287.93mg%. The Hunter a and b values gradually increased during the fermentation, but the L value decreased until day 30 or 40 and increased steadily after that. The a and b values were higher in the use of Asp. oryzae koji than in Bccillus sp. koji, but the L value was to the contrary. The Asp. oryzae koji added anchovy paste was good in the aspect of color and taste compared to others. In the aspect of odor, the anchovy paste using the mixture of Asp. oryzae and Bacillus sp. koji was the best. Overall aceptability of sensory evaluation was higher in the mixture of Asp. oryzae and Bacillus sp. koji tan in the others.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.22 no.1
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• pp.25-35
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• 1989

To prepare a new type of fish sauce from skipjack scrap, it was examined the effect of koji on the sauce flavor, conditions of low salt fish sauce processing and the changes of taste com-pounds during its fermentation. To prepare the skipjack scrap sauce, chopped skipjack head paste was mixed with $6.6\%$ skipjack viscera, $26.9\%$ koji, $71\%$ of $25\%$ brine, $13.3\%$ salt and $7.6\%$ glucose, and fermented at $25\pm4^{\circ}C$ for 90 days. The same process was also carried out to prepare the low salt skipjack scrap sauce adding $7.6\%$ sorbitol, $0.3\%$ lactic acid and $9.8\%$ ethyl alcohol instead of $13.3\%$ salt. The major free amino acids in the products were glutamic acid, Iysine, valine, phenylalanine, alanine, leucine and isoleucine at 90 days of fermentation. And the contents of total free amino acids in both products were 3,307mg/00m1, 3,637.1mg/100m1 at 90 days of fermentation. The predominating non-volatile organic acids showed in the products were lactic acid, succinic acid, pyroglutamic acid, which were $90\%$ over contents of the total non-volatile organic acids. Total non-volatile organic acid contents in both products were 1,002.1mg/100ml, 1,312.9mg/100m1 at 90 days of fermentation. During fermentation of sauce, ADP, AMP and IMP were decreased, while inosine and hypoxanthine were increased. The major taste compounds of the products were rove진ed free amino acids and non-volatile organic acids. The nucleotides and their related compounds, total creatinine, betaine, TAMO and sugar were seemed to be having an auxiliary role in taste of those products. Fishy odor in skipjack scrap sauce can be improved by adding koji. And the low salt skipjack scrap sauce ($9.12\%$ of salt contents) can be prepared by the replacement of a part of salt with sorbitol, lactic acid and ethyl alcohol. From the results of sensory evaluation and chemical experiments, the skipjack scrap sauce products supposed to be at least equal to the sold soy sauce on the market in quality.

• Korean Journal of Food Science and Technology
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• v.26 no.1
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• pp.12-17
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• 1994

Physicochemical characteristics of traditional kochujang fermented for 6 months and commercial kochujang were compared. Tested kochujang included 18 kinds of Sunchang kochujang prepared with glutinous rice, 10 kinds of Boeun kochujang prepared with barley and 17 kinds of Sachun kochujang prepared with wheat, and 10 kinds of commercial kochujang. Major free sugar was found to be glucose both in traditional and commercial kochujang. Fructose, maltose, and sucrose were also detected in small amounts. The contents of free sugars in traditional kochujang was approximately one fourth of those presented in commercial kochujang. Commercial kochujang showed the highest level of total free amino acids followed in decreasing order by Sachun, Sunchang, and Boeun kochujang. The most abundant free amino acid was serine in Sunchang kochujang and aspartic acid both in Boeun and Sachun kochujang. On the other hand, glutamic acid was the most abundant amino acid in commercial kochujang. Volatile organic acids in various kochujang were determined and acetic, propionic, butyric, and 3-methyl butanoic acids were found in traditional kochujang. However, 3-methyl butanoic arid was not found in commercial kochujang. The most abundant volatile acid was acetic acid in both tradtional and commercial kochujang. Analysis of non-volatile organic acids showed that large amounts of lactic, oxalic, and succinic acids were found in traditional and commercial kochujang. In addition to these, small amounts of itaconic, malic, malonic, and pyroglutamic acids were found in commercial kochujang.

• Food Science of Animal Resources
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• v.31 no.5
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• pp.710-718
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• 2011

The effects of organic acids mix (0.4%) and modified atmosphere packaging (MAP) on the storage quality of sliced bacon were investigated. Pork bellies were treated with or without organic acids at the curing stage. The organic acids mix comprised 35% sodium acetate, 25% salt, 15% calcium lactate, 11% trisodium citrate, 7% ascorbate, and 7% citric acid. The cured pork bellies were smoked and packaged with 50% $CO_2$ + 50% $N_2$ (50% $CO_2$-MAP) and 100% $N_2$ (100% $N_2$-MAP), and stored at $5^{\circ}C$ for 14 d. The 50% $CO_2$-MAP showed a higher pH value (p<0.05) up to 10 d, a lower protein deterioration (p<0.05) as measured by volatile basic nitrogen (VBN) from 6 to 14 d, and a higher color value of lightness (CIE $L^*$) compared to 100% $N_2$-MAP. The development of lipid oxidation measured by thiobarbituric acid reactive substance (TBARS) values seemed to be effectively controlled throughout the storage period in both 50% $CO_2$-MAP and 100% $N_2$-MAP regardless of the application of organic acids. The 50% $CO_2$-MAP inhibited the growth of aerobic and anaerobic bacteria (p<0.05) both in non-added and bacon added with organic acids mix. The 50% $CO_2$-MAP alone seemed to be effective in delaying the growth of bacteria since the use of organic acids mix gave no additional effects. The addition of organic acids mix lowered the pH value (p<0.05), effectively retarded the protein deterioration (p<0.05), and showed a higher color value of lightness (CIE $L^*$) value (p<0.05) and lower color value of redness (CIE $a^*$) value (p<0.05). In conclusion, 50% $CO^2$-MAP showed better quality and self-life of sliced bacon during storage. However, the beneficial effect of organic acids mix was not noticed in the concentration used in this experiment.

• Microbiology and Biotechnology Letters
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• v.43 no.3
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• pp.227-235
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• 2015

The objective of this study was to improve the quality of Korean rice wine with wild type yeast strains isolated from various traditional Korean fermented foods. Herein the fermentation and sensory characterization of wild yeast, for the purposes of brewing Korean rice wine, was investigated. 12 yeast strains were examined for their ethanol and glucose tolerance. In addition, the pH, soluble solids, acidity, amino acidity, ethanol content, organic acids, and volatile compounds were also studied for the alcoholic beverages made with the wild yeasts. Almost all Saccharomyces genera yeasts were showed to have a tolerance at 10% ethanol, but non-Saccharomyces genera yeasts displayed a low tolerance. The alcoholic beverages fermented by non-Saccharomyces yeasts demonstrated higher levels of soluble solids, titratable acidity, amino acids, and lower ethanol content, when compared with the alcoholic beverages fermented by Saccharomyces genera yeasts. The organic acid content, such as malic acid, acetic acid, and succinic acid, was seen to also be higher. The electronic nose was analyzed, and discriminant function analysis (DFA) was used for discriminating wild yeast strains. The DFA plots indicated a significant separation of Saccharomyces genera and non-Saccharomyces yeast strains. For volatile compounds, ethyl acetate from non-Saccharomyces yeasts, and ethanol from Saccharomyces genera yeast, a high area ratio was observed.