• Journal of Microbiology and Biotechnology
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• v.23 no.2
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• pp.189-194
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• 2013

In a study of hydrogen-producing bacteria, strain T4384 was isolated from rice field samples in the Republic of Korea. The isolate was identified as Enterobacter sp. T4384 by phylogenetic analysis of 16S rRNA and rpoB gene sequences. Enterobacter sp. T4384 grew at a temperature range of $10-45^{\circ}C$ and at an initial pH range of 4.5-9.5. Strain T4384 produced hydrogen at 0-6% NaCl by using glucose, fructose, and mannose. In serum bottle cultures using a complete medium, Enterobacter sp. T4384 produced 1,098 ml/l $H_2$, 4.0 g/l ethanol, and 1.0 g/l acetic acid. In a pH-regulated jar fermenter culture with the biogas removed, 2,202 ml/l $H_2$, 6.2 g/l ethanol, and 1.0 g/l acetic acid were produced, and the lag-phase time was 4.8 h. Strain T4384 metabolized the hydrolysate of organic waste for the production of hydrogen and volatile fatty acid. The strain T4384 produced 947 ml/l $H_2$, 3.2 g/l ethanol, and 0.2 g/l acetic acid from 6% (w/v) food waste hydrolysate; 738 ml/l $H_2$, 4.2 g/l ethanol, and 0.8 g/l acetic acid from Miscanthus sinensis hydrolysate; and 805 ml/l $H_2$, 5.0 g/l ethanol, and 0.7 g/l acetic acid from Sorghum bicolor hydrolysate.

• Journal of Environmental Science International
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• v.24 no.4
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• pp.549-554
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• 2015

This study was conducted to determine the effects of mixed Korean red ginseng marc with aluminum sulfate on gas concentration and volatile fatty acid (VFA) in poultry litter during 4 weeks in terms of livestock and environment managements. A total of 240 broiler chicks were randomly allocated to four treatments in four replications and 15 birds per replicate. The four treatments was mixed to rice hull under each pen at 0, 10 g or 20 g red ginseng marc + 90g aluminum sulfate, and 100g aluminum sulfate per kg poultry litter (rice hulls). Carbon dioxide, methane, acetic acid, and propionic acids were measured weekly. The results that could be available include: First, during the experimental period, carbon dioxide emissions were not remarkably different among treatments. Second, no differences were observed among treatments in methane emissions at 2 weeks through 4 weeks, but at 1 week, the reduction in methane emissions was in following order: 100 g aluminum sulfate > 20 g red ginseng marc + 90 g aluminum sulfate > 10 g red ginseng marc + 90 g aluminum sulfate > control. Third, in spite of statistically differences, treatment with 10 g or 20 g red ginseng marc + 90g aluminum sulfate, and 100g aluminum sulfate reduced acetic acid and propionic acid as a function of time, except acetic acid in aluminum sulfate treatment at 2 and 4 weeks. In conclusion, the results indicated that like aluminum sulfate, using 10 g or 20 g red ginseng marc with aluminum sulfate was effective in decreasing methane and propionic acid released from poultry litter.

• Food Science of Animal Resources
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• v.40 no.4
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• pp.527-540
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• 2020

Donkey in China is well known for its draft purpose and transportation; however, donkey meat has attracted more and more consumers in recent years, yet it lacks sufficient information on its flavor components compared to other main meats. Therefore, in this study, volatile flavor compounds in neck meat of donkey, swine, bovine, and sheep were classified by electronic nose, then confirmed and quantified by gas chromatography-mass spectrometry. High-performance liquid chromatography (HPLC) and gas chromatography were used to quantify free fatty acid, amino acid, and flavor nucleotide. A total of 73 volatile compounds were identified, and aldehydes were identified as the characteristic flavor compounds in neck meat of donkey, bovine, swine and sheep in proportion of 76.39%, 46.62%, 31.64%, and 35.83%, respectively. Particularly, hexanal was the most abundant volatile flavor. Compared with other neck meat, much higher unsaturated free fatty acids were present in donkeys. Furthermore, neck meat of donkeys showed essential amino acid with highest content. Thus, special flavor and nutrition in donkey neck meat make it probably a candidate for consumers in other regions besides Asia.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.1
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• pp.61-66
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• 1985

Cooked rice was prepared by the conventional cooking method being used among Korean families. The bottom layer (very slightly roasted and charred) and upper layer of the cooked rice in a cooking vessel were collected separately in order to determine the chemical changes and volatile carbonyl formation occurring in rice during the cooking process. Amino acids, especially free amino acid contents were reduced with the decrease of reducing sugar in rice after cooking. A little change was shown in the fatty acid composition of lipid fractions, however, decreased iodine values and increased fatty acid values were observed after cooking process. Volatile carbonyl compounds from cooked rice were isolated and 8 carbonyls of them were identified. A significant difference of relative composition of the identified carbonyls was found between the upper layer and bottom layer of cooked rice. Generally, the cooked rice obtained from the bottom layer had shown a little more changes in chemical composition and a stronger browning flavour than those of the upper layer of cooked rice.

• Journal of Life Science
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• v.11 no.6
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• pp.517-522
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• 2001

To Confirm the repression of off-odor and improvement of food quality in small black bean chungkugjang (SBC), some taste compounds of SBC added with kiwi and radish homogenate and fermented fro 3 days at 42$^{\circ}C$ were investigated. Contents of free amino acids in SBC were lower than that of soybean chungkugjang (SC) and were increased by adding kiwi and radish homogenate to black bean, indicating that two materials were effective to the enzymatic digestibility of soy protein. Of organic acids, citric acid was the most abundant, followed by acetic acid and lactic acid. Fatty acid composition was high in the order of linoleic acid (50.82~54.51%), oleic acid (17.76%~22.10%) and plamitic acid(12.13~13.79%). There were no significant difference in compositions of organic acids and fatty acids of chungkugjang. Major volatile compounds of SBC were indole , 2-5-dimethyl pyrazine and trimethyl pyrazine. Contents of alkyl pyrazines that contribute the characteristic aroma and flavor of SBC added and fermented with kiwi and radish homogenate were 3 times lower than those of SC. Uracil and UMP were major nucleic acie-drlated compounds in all four chungkugjangs. Contents of the other nucleic acid-related compounds were a similar trend in all chungkugjangs.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.1
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• pp.61-65
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• 2005

The objective of this work was to investigate the nutritional requirements for the growth of Actinomyces sp. 9RCC5 isolated from the rumen of a native goat in Korea. The growth of strain 9RCC5 on the basal medium or the medium minus certain ingredients from the basal medium demonstrated that strain 9RCC5 showed absolute requirement of vitamin B complex mixture, while hemin and volatile fatty acids (VFA) were stimulatory to growth to some extent. The 9RCC5 strain grew well with casein hydrolysate as the sole added nitrogen source. However, neither a complex of 18 amino acids nor ammonium sulfate effectively replaced casein hydrolysate. Vitamins such as riboflavin and pantothenate were essential for growth, while thiamin and biotin were stimulatory. With regard to VFA, the growth was stimulated by acetic acid but inhibited by valeric acid. Relatively large quantities of $Na^+$, $K^+$ and $Ca^{2+}$ were absolutely required for growth. Supplementation of clarified rumen fluid to the basal medium in a range of 0-10% (vol/vol) resulted in an increased rate of growth as well as an increased extent of growth.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.8
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• pp.1084-1093
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• 2000

An in vitro gas production system was used to investigate the influence of various substrate mixtures on a natural mix of rumen microbes by measurement of fermentation end-products. The treatments were combinations of cassava (15.0, 30.0 and 45.0%) with different roughage sources (ruzi grass, rice straw or urea treated rice straw). Microbial biomass, net $^{15}N$ incorporation into cells, volatile fatty acid production, gas volume and rate of gas production increased linearly with increasing levels of cassava inclusion. There was also an effect of roughage source, with rice straw being associated with the lowest values for most parameters whilst similar values were obtained for ruzi grass and urea treated rice straw. The results suggest that microbial growth and fermentation rate increase as a function of readily available carbohydrate in the substrate mixture. A strong linear relationship between $^{15}N$ enrichment, total volatile fatty acid production and gas production kinetics support the suggestion of the use of the in vitro gas production system as a tool for screening feedstuffs as an initial stage of feed evaluation.

• Journal of the Korean Society of Food Culture
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• v.21 no.1
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• pp.81-85
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• 2006

Seasoning oil(SO-1) was manufactured from soybean oil, with ${\beta}-carotene$, oleoresin paprika and 3 kinds of flavors. Color of it's SO-1 was red. Total content of trans fatty acid of SO-1 was low level 0.84%, compare to the butter's and margarine's 1.35%, 28.31%, respectively. Total volatile components of SO-1 was 201,313.11ppm, was higher than soybean oil's, butter's, margarine's and SO-2's(removed 3 kinds of flavors from SO-1), it's value of 63.54ppm, 481.24ppm, 168.95ppm and 205.73ppm, respectively. And smoke point(SP) of SO-1 was higher than others. SP of SO-1, after 6 months later at room temperature, was 240, in contrast with soybean oil's 228. This SO-1, added ${\beta}-carotene$ and flavor components, had a masking effect of burnt flavor. From these results, SO-1 can be replaced of butter or margarine as a substituted oil.

• Journal of Animal Environmental Science
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• v.19 no.1
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• pp.1-8
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• 2013

Slurry treatments included peanut shell, palm golden fiber, almond hull, which was added 2% of the amount of slurry, and non-treatment control (n=4 each group). Levels of odorous compounds were measured from the liquid slurry incubated in $20^{\circ}C$ for 2 wk in chamber whose structure is similar to slurry pit. Concentration of phenols and indoles was higher (p<0.05) in control (48.4, 4.0 ppm) compared to almond hull (31.5, 1.4 ppm) or palm golden fiber (29.1, 1.6 ppm) group. Short chain fatty acid (SCFA) level was lowest (p<0.05) in control (2,121 ppm) but highest in peanut shell group (3,640 ppm). Branched chain fatty acid (BCFA) concentration was highest (p<0.05) in peanut shell (296 ppm), but lowest in almond hull (90 ppm). Taken together, concentration of odorous compounds was decreased by addition of almond hull in pig slurry by which crude fiber and non-digestible fiber (NDF) may act as a carbon source.

• Food Science of Animal Resources
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• v.42 no.3
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• pp.504-516
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• 2022

This study aimed to investigate the effect on the chemical quality of whey and Ricotta obtained from ewes fed a red grape pomace (GP) dietary supplementation. The analyses were performed on whey, before and post Ricotta cheese-making, and in Ricotta after 1 (T1) and 5 (T5) d of ripening at 4℃. Moreover, fatty acid profile of whey before ricotta (WBR) cheese-making and Ricotta T1 of ripening and volatile profile of Ricotta T1 and T5 were investigated. The diet did not affect whey and Ricotta lipid content, conversely, significant variations were instead observed with regard to color. A lower amount of total phenolic compounds was found in WBR cheese-making, on the contrary, an opposite trend was highlighted in Ricotta T1 although no variations in antioxidant properties were detected. Moreover, GP modified fatty acid profile of whey and Ricotta but did not have any effect on protein profile of the main whey protein. The reduction of hexanal in Ricotta during the ripening suggest a better oxidative stability. The obtained results therefore suggested that the GP inclusion in the ewes diet, while modifying some chemical parameters, did not induce negative effects on the characteristics and quality of dairy by-products.