• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1204-1210
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• 2013

Various commercial vinegars of high-strength acidity (10% or more of total acidity) were investigated to compare their physicochemical and antioxidant properties. The total acidity of double-strength vinegars was relatively lower than triple-strength vinegars. Irrespective of the acidity, sugar and reducing sugar content ranged from $7.00{\sim}10.80^{\circ}Bx$ and 1.32~3,885.90 mg%, respectively. Free sugars were mainly composed of fructose and glucose, and were relatively high in double-strength vinegars. The content of acetic acid (a principal organic acid in vinegars) increased with acidity, but oxalic acid was not identified in commercial high-strength acidity vinegars. Double-strength vinegars using malt extracts were the highest in free amino acid content, showing 24 kinds of amino acids. The content of total phenolics and flavonoids was highest in apple vinegars of double-strength acidity, which affected the scavenging ability of DPPH and ABTS radicals. Overall, the quality of high-strength acidity vinegars was affected by its content and production methods, and double-strength acidity vinegar using apples showed the best antioxidant activities.

• Korean Journal of Food Science and Technology
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• v.39 no.6
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• pp.676-680
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• 2007

This research was conducted to investigate the changes in quality characteristics of cheonggukjang made with 24-hr germinated soybeans during fermentation. Our study confirmed that the pH of the 24-hr germinated soybeans was 6.7, and the value increased as fermentation progressed. The amount of viscous substances in the cheonggukjang produced with the 24-hr germinated soybeans constantly increased to 5.89% at 36 hr of fermentation, and then remained unchanged. Free sugars (raffinose, sucrose, glucose, and fructose) rapidly decreased with the fermentation process. The levels of free amino acids in the 24-hr germinated agakong and the 48-hr fermented cheonggukjang were 391.0 and 10,994.8 mg%, respectively. Glutamic acid content was highest, followed by aspartic acid, lysine, leucine, and proline. The ratio of glutamic acid to total free amino acids at 48-hr of fermentation was 18.0%. Finally, it was confirmed that the sensory evaluation score of the 24-36 hr fermented cheonggukjang, made with the 24-hr germinated soybeans, was superior to that of the 24 and 48-hr fermented cheonggukjang.

• Horticultural Science & Technology
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• v.29 no.2
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• pp.144-150
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• 2011

This study was conducted to investigate the nutrient components and physicochemical properties of general ('Superior') and colored potato. Proximate composition, reducing sugar, free sugars, free amino acids, organic acids, minerals were analyzed, and Hunter color values were measured in the study. 'Rose' and 'Blue' (colored potatoes) contained high levels of reducing sugar, and total free sugar content was greatly different according to varieties. Glutamic acid, arginine and ${\gamma}$-aminobutyric acid were detected to be the three major amino acids in colored potato, and the major organic acids of general potato were oxalic acid, tartaric acid, malic acid and citric acid. All potato contained high level of potassium, calcium and magnesium. The Hunter 'L' value was the highest in 'Jaseo'; Hunter 'a' value was high in 'Blue' and 'Jasim'; Hunter 'b' value was the highest in 'Haryoung'. Overall, colored potato had higher amount of nutrients and physicochemical properties than 'Superior'. Therefore, colored potatoes are expected to be highly valuable items for the development and applications of a functional food. In addition, these results will provide fundamental data for improving sitological value, breeding of new cultivar and promoting of roughage usage.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.28-32
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• 2003

As part of studies on the high quality dunggule tea, made of Polygonatum odoratum root with different growth year were analyzed for their flavor compounds. The quality attributes related to flavors were compared between raw and roasted samples which were treated at $130^{\circ}C$ for 15 min. Free sugars in the roots were mainly composed of fructose ($3.59{\sim}4.83%,\;d.b.$), sucrose ($1.78{\sim}2.49%$), and glucose ($1.60{\sim}1.80%$). Threonine ($1,239{\sim}1,444\;mg/100g,\;d.b.$), arginine ($589{\sim}689$), histidine ($289{\sim}370$) were three major free amino acids. The root grown for three years showed the highest content in total free sugar and amino acids (p<0.05). There was negligible difference in proximate composition and Hunter's color parameter depending on the growth year of the roots. However, sensory scores on color, taste and aroma were highest in 3 years' root, which is found most suitable for the preparation of dunggule tea. The roasting of 3 years old root significantly reduced the content of fructose and sucrose (p<0.01). It caused most apparent changes in the decreasing amount of threonine and in the decreasing rate of lysine, showing the significant decrease in total free amino acid content (p<0.01).

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.520-527
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• 1987

This study was attempted to identify microorganisms in fermenting soybean curd residues (SCR). The changes in contents of free amino acids, nucleosides, reducing sugars, and oligosaccharides were also studied. The fermentation of SCR which was by change inoculation was carried out at $55^{\circ}C$ for 48 hrs. pH increased gradually during fermentation and isolated microorganisms were identified as Bacillus subtilis and Bacillus licheniformis. Moisture content decreased from 80.8% to 58.4% at 48 hrs of fermentation and other proximate composition did not show any changes during fermentation. The content of total free amino acids increased rapidly and the number and quantities of each amino acid analyzed also increased during the course of fermentation. Glutamic acid, phenylalaine, lysine and aspartic acid were rapidly liberated during fermentation. As to the changes of nucleotides, 5'-AMP little changed during the first 36 hrs but subsequently decreased to approximately 1/6 after 48 hrs of fermentation. On the other hand, 5'-IMP plus 5'-GMP did not show almost any change during the first 36 hrs but increased about 3.5 times at 48 hrs of fermentation. However, 5'-XMP was not detected. The reducing sugar level showed rapid and steady increase throughout the fermentation and that of stachyose plus raffinose decreased slightly. From these results, a possible way of utilization of fermented SCR was proposed as a substitute for soybean in meju preparation.

• KSBB Journal
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• v.32 no.1
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• pp.63-70
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• 2017

Bamboo leaf has many nutritional and bioactive compounds such as polyphenols, and it can be used for various foods application. Fermentation is one of appropriate processes that can affect the nutrition, taste and flavor, and antioxidant activities of foods. In this study, a representative domestic bamboo tree (Sasa coreana Nakai) leaves were fermented by Bacillus subtilis KCCM 11315 and the changes of carbohydrates, minerals, amino acids, and phenolic compounds and antioxidant activities were investigated before and after fermentation. During the fermentation period, firstly, the leaf was softened and turned to brown. The constituent carbohydrates were slightly increased from $432.09{\pm}5.38mg/g$ to $458.42{\pm}7.39mg/g$, and free sugars decreased by 95% from $28.12{\pm}2.03mg/g$ to $1.4{\pm}0.14mg/g$. Mineral was $20987.5{\pm}345.1{\mu}g/mL$, which was slightly increased after the fermentation compared to $20804.1{\pm}364.6{\mu}g/mL$ before that. The total amino acids were increased to $73881.94{\pm}137.59mg/100g$ compared to $58464.51{\pm}109.12mg/100g$ before fermentation, and free amino acids decreased by more than 85% from $32782.67{\pm}92.49mg/100g$ to $4827.83{\pm}19.76mg/100g$. Total polyphenols content (TPC) increased from $25.51{\pm}1.04GAE^*mg/g$ to $35.34{\pm}0.91GAE^*mg/g$, and the total flavonoid content (TFC) increased to $80.57{\pm}0.22QE^*mg/g$ compared to $69.64{\pm}0.26QE^*mg/g$. The total catechin content (TCC) of TFC was decreased from $69.64{\pm}0.94mg/L$ to $58.23{\pm}0.76mg/L$. The DPPH radical $IC_{50}$ of bamboo leaves decreased to $2624.85{\pm}37.03{\mu}g/mL$ and the ABTS radical $IC_{50}$ of $187.26{\pm}4.78{\mu}g/mL$ was increased after the fermentation. These results could be used as essential nutritional data before developing processed food products using the bamboo leaf.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.957-966
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• 2017

Objective: To understand the dynamic structure, function, and influence on nutrient metabolism in hosts, it was crucial to assess the genetic potential of gut microbial community in yaks of different ages. Methods: The denaturing gradient gel electrophoresis (DGGE) profiles and Illumina-based metagenomic sequencing on colon contents of 15 semi-domestic yaks were investigated. Unweighted pairwise grouping method with mathematical averages (UPGMA) clustering and principal component analysis (PCA) were used to analyze the DGGE fingerprint. The Illumina sequences were assembled, predicted to genes and functionally annotated, and then classified by querying protein sequences of the genes against the Kyoto encyclopedia of genes and genomes (KEGG) database. Results: Metagenomic sequencing showed that more than 85% of ribosomal RNA (rRNA) gene sequences belonged to the phylum Firmicutes and Bacteroidetes, indicating that the family Ruminococcaceae (46.5%), Rikenellaceae (11.3%), Lachnospiraceae (10.0%), and Bacteroidaceae (6.3%) were dominant gut microbes. Over 50% of non-rRNA gene sequences represented the metabolic pathways of amino acids (14.4%), proteins (12.3%), sugars (11.9%), nucleotides (6.8%), lipids (1.7%), xenobiotics (1.4%), coenzymes, and vitamins (3.6%). Gene functional classification showed that most of enzyme-coding genes were related to cellulose digestion and amino acids metabolic pathways. Conclusion: Yaks' age had a substantial effect on gut microbial composition. Comparative metagenomics of gut microbiota in 0.5-, 1.5-, and 2.5-year-old yaks revealed that the abundance of the class Clostridia, Bacteroidia, and Lentisphaeria, as well as the phylum Firmicutes, Bacteroidetes, Lentisphaerae, Tenericutes, and Cyanobacteria, varied more greatly during yaks' growth, especially in young animals (0.5 and 1.5 years old). Gut microbes, including Bacteroides, Clostridium, and Lentisphaeria, make a contribution to the energy metabolism and synthesis of amino acid, which are essential to the normal growth of yaks.

• Clean Technology
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• v.17 no.4
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• pp.395-405
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• 2011

To develop the technology for cultivation of high-density seaweed, sea tangle was cultured from varying depths(0.5 m, 3 m) of seawater at Gijang and Wando area. Proximate composition, component sugar, total amino acid, fatty acid composition, and element composition of different parts of sea tangle (Saccharina japonica) have been examined. Significant differences were found in the amount of crude protein and ash content in lower, middle, and upper parts of algal blades. The upper parts of the sea tangle was rich in crude protein, while lower parts was rich in crude ash. Crude lipid content was higher in the middle parts than those of the other parts. The component sugars were not significantly different from all parts of algal blades. The highest content of most of the amino acids were found in the upper parts of the blades. The amount of saturated fatty acids concentrated mostly in lower parts of blades, while the content of polyunsaturated fatty acids concentrated in the upper parts. The highest N element contents were found in upper part of algal blades. However, the contents of those chemical component were not affected by the depths of seawater.

• Food Science and Preservation
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• v.9 no.2
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• pp.228-233
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• 2002

In order to exploit as a new functional decocted beverage, chemical components, antioxidative and antimicrobial activities young stems of mulberry(Morus alba) were surveyed. The proximate composition was composed of crude fiber 51.12%, ash 13.46%, total sugar 10.38%, crude fat 9.10% and crude protein 5.01%. The P(295.9 mg%) was the highest mineral found in young stem of mulberry and Ca 289.6 mg%, K 209.6 mg%, Na 58.3 mg%, Mg 45.0 mg% and Fe 4.6 mg% in that order. Free sugars was composed of glucose 1.08%, galactose 022%, sucrose 0.20% and fructose 0.16%. Eight fatty acids in stem of mulberry were identified and the major fatty acids were linoleic acid(46.10%), palmitic acid(27.84%) and linolenic acid(10.85%). Among the 17 amino acids detected, total amino acid was 2,450.5 mg% and proline(313.7 mg%) was the most predominant. Methanol extract and ethyl acetate fraction showed stronger activity of the hydrogen donating activities, each of 77.24% and 80.08%, respectively. The methanol extract from young stem of mulberry showed the strongest antimicrobial activities to Bacillus subtitis and Bacitus cereus. Chloroform and ethyl acetate fractions from methanol extract of young stem showed a inhibition zone of 9.0∼19.0 ㎜ in diameter against pathogen bacteria.

• Korean Journal of Food Science and Technology
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• v.33 no.2
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• pp.264-270
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• 2001

In order to improve the quality of traditional kochujang, condiments like garlic and onion were added to kochujang and their effect on microbial characteristics, enzyme activities and taste components were investigated during fermentation. Viable cells of yeasts in the kochujang decreased with the increasing ratio of garlic. However, aerobic and anaerobic bacterial counts did not show any remarkable differences in the garlic or onion added kochujang, they decreased slowly after $6{\sim}10$ weeks of fermentation. The activity of liquefying amylase in kochujang decreased slowly during $2{\sim}10$ weeks of fermentation, but that of saccharifying amylase increased remarkably at $14{\sim}18$ weeks. Amylase activities increased at the late period of fermentation in garlic or onion added kochujang. Protease activities of kochujang were strong in the middle of fermentation, but they decreased by addition of garlic or onion. The major free sugars in kochujang were glucose and fructose, and their contents increased as the ratio of garlic increased. The major organic acids in kochujang were succinic, malic and oxalic acid, and they also decreased by addition of garlic and onion. The contents of total free amino acids and amino nitrogen were the highest in 2% garlic added kochujang. The major free amino acid were glutamic acid, aspartic acid, proline, alanine, leucine, isoleucine and arginine. Serine, glutamic acid, lysine and arginine contents in increased by adding garlic or onion.