• The Korean Journal of Food And Nutrition
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• v.13 no.2
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• pp.118-124
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• 2000

Lipoxygenase(LOX) in soybeans is responsible for beany flavors which limit the wide utilization of soybeans to foods. This study was conducted to analyze beany flavor compounds of the normal Hwagkeumkong and LOX-deficient soybean cultivars, Jinpumkong which lacks L-2, L-3, and Jinpumkong 2 which lacks all L-1, L-2, L-3. Using the combination of dynamic headspace sampling and gas chromatography-mass selective detector(DHS-GC-MSD) for analyzing volatile compounds, hexanal and hexanol were identified in whole soy flour of all three soybena cultivars. Hwangkeumkong had more volatile compounds than Jinpumkong and Jinpumkong 2 in defatted soy flour. Hexanal and acetic acid were identified in soy milk of all three soybean cultivars but Hwangkeumkong had more volatile compounds than Jinpumkong 2. From the analysis with a static headspace sampling(SHS) and GC-MSD the major compounds were hexanal, acetic acid, 1-hexanol, and 1-octen-3-ol. The content of acetic acid was similar among three cultivars. But contents of hexanal and pentanal in Jinpumkong 2 were less than that of Jinpumkong and Hwangkeumkong. Using GC-FID, Jinpumkong 2 had less contents of hexanal and pentanol than Hwangkeumkong in whole soy flour and defatted soy flour. In this study, LOX-deficient soybean cultivars showed less hexanal, pentanol and other compounds than the normal Hwangkeumkong. However quite amount of beany flavor compounds were identified in Jinpumkong and Jinpumkong 2. So further studies are required to characterize LOX isozymes, to understand the mechanisms of beany flavors production, and to develop some other methods for removing beany flavor.

• Membrane Journal
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• v.14 no.1
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• pp.37-43
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• 2004

As the experimental results of membrane application for the production and recovery of volatile fatty acids, suspended solids concentration, the number of acid producing bacteria and organic acid concentration increased with membrane coupling in the fermenter. The application of membrane for the efficiency increase of solid-liquid separation and fermentation made the number of acid producing bacteria increase in the fermenter, thus acid forming rate showed higher value than that of membrane-free fermenter. Membrane-coupled fermenter was believed to be an effective technology for the improvement of recovery efficiency of volatile fatty acids from organic sludge.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.300-306
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• 1993

Speries-related meat flavors were investigated for red meats (bovine, porcine, caprine, and ovine). Volatile branched-chain fatty acids (VBCFAs) including 2-methylbutanoic, 3-methylbutanoic, 4-methylpentanoic, 2-ethylhexanoic, 4-methylhexanoic, 4-methyloctanoic, 6-methyloctanoic, 4-ethyloctanoic, 4-methylnonanoic, and 2-ethyldecanoic acids were identified in the meats from cow (bovine), pig (porcine), goats (caprine ; American white goat and Korean black goat), and lamb (ovine). Beef flavor of bovine meat was characterized by the basic meaty flavor, lacking in goaty and muttony flavor impacts due to low or absent in 4-methyl.octanoic and 4-ethyloctanoic acids. Porcine meat contained the least number of VBCFAs among sample species tested, and 3-methylbutanoic acid contributed to the unclean sweaty odor of pork. Caprine meat from Korean black and American white goats lacked in short VBCFAs (C5, C6, and C7) and contained 4-methyloctanoic and 4-ethyloctanoic acids contributing to the characteristic goaty flavor of caprine meat. Caprine meat flavor was distinctively characterized by 4-ethyloctanoic acid, while 4-methyloctanoic acid provides sweaty-muttony flavor to ovine meat. Although kinds of VBCFAs are same in two different varieties of caprine meats, meat sample from Korean black goat had stronger goaty odor and contained higher concentration of 4-ethyloctanoic acid than the meat sample from American white goat did.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.370-374
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• 1989

This study was conducted to examine the effects of salt concentrations (1,2 and 37)) and storage periods on the characteristics of Kakdugi (Korea seasoned pickles of cubed radish roots) stored at $20^{\circ}C$. The sensory characteristics, pH, titratable acidity, non-volatile organic acids were measured. The results of sensory evaluation on Kakdugi containing 1,2 or 30% sodium chloride stored for 4 or 8 days indicated that there were significant differences among them expecially ill firmness, crispness and salty taste. As storage period increased, titratable acidity, sour taste, non-volatile organic acid contents of the samples increased. The changes were greater in Kakdugi with 2% sodium chloride. Major non-volatile organic acids were identified as lactic acid, citric acid and succinic acid. The sour taste of Kakdugi was closely related to the contents of non-volatile organic acid and titratable acidity.

• Korean Journal of Food Science and Technology
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• v.41 no.6
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• pp.615-621
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• 2009

In order to optimize the supercritical fluid extraction (SFE) conditions of volatile components from the strawberry, we conducted an evaluation of the sample preparation and SFE operating conditions. The analysis of the volatile components extracted by a variety of sample preparation protocols led to the identification of 30, 26, 30, and 34 volatile components in fresh, freeze-dried, 30% celite and 70% celite treatments, respectively. The 70% celite treatment was the most effective in extracting the volatile components from strawberry via SFE. Analysis of the volatile components extracted by a variety of SFE operating conditions yielded identifications of 34, 35, 34, and 35 volatile components at 3,000 psi (40, $50^{\circ}C$) and 6,000 psi (40, $50^{\circ}C$), respectively. The extraction yield of alcohols and acids, and the total volatile component contents, were highest under conditions of 3,000 psi and $55^{\circ}C$. Volatile components from the strawberry were extracted via SFE, simultaneous steam distillation and extraction (SDE), and solvent extraction (SE). The analysis of the volatile components extracted via different extraction methods resulted in the identification of 56, 34, and 32 volatile components in the SDE, SFE, and SE extracts, respectively. The total volatile component contents identified in the SDE, SFE, and SE extracts were $20.268{\pm}1.144$, $21.627{\pm}1.215$ and $2.476{\pm}0.177\;mg/kg$, respectively. The SFE extract evidenced higher contents of sweet flavors such as 2-methylbutanoic acid, 2-methylpropanoic acid, and hexanoic acid than the SDE and SE extracts. SFE proved to be the most appropriate method for the extraction of fresh volatile components from the strawberry.

• Food Science and Preservation
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• v.7 no.1
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• pp.108-112
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• 2000

Proximate composition , volatile compounds, free amino acids, fatty acids and inorganic compounds in leaf, stem and root of Houttyunia cordata Thunb cultivated from two different area, Bosung and Sunchon , were analyzed. Each part of Houttuynia cordata Thunb from both local area showed moisture contents of 80-84% and crude ash contents of 2.1 ∼2.8%. Crude fat and protein contents were less than 3 % showing slightly higher contents in leaf than in both stem and root . Twenty six volatile compunds were identified from the parts of the plant, the volatile contents were high in the oder of leaf, root and stem. Major volatile compounds were mostly derivatives of decanoic acid ; decanoic acid, 20 tridecanoie, decanal and dodecanoic acid. Of free amino acids in leaf asparagine was the highest, while in stem hydroxyproline, proline and arginine were the major free amino acids. Linoleic acid was the highest in the stem and root, and linolenic acid was highest in leaf. the major minerals of all parts were K, Ca. Mg, P, Fe, Zn and Cu, showing highest with K.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.384-388
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• 1996

Volatile flavor compounds of a sea tangle powder and two kinds of extract were analyzed by GC/MS. Extract I was prepared by boiling for 2 hours and centrifugation, while extract II by a sequential procedure of enzymatic hydrolysis, boiling in 1.5% NaCl solution. centrifugation and ultrafiltration to remove viscous materials. Fifty six volatile compounds from the dried sea tangle powder and the extracts were identified. The GC profiles of the extract II were different from those of the dried powder and the extract 1, indicating most volatile compounds were lost during removing viscous materials. Particularly those compounds in the initial and later parts of the GC profiles were significantly decreased and some of the compounds such as fatty acids. 3,5-nonadien-2-ol and 1-penton-3-ol were not detected.

• The Korean Journal of Food And Nutrition
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• v.13 no.5
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• pp.453-459
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• 2000

In order to promote the utilization of Rubus coreanum as functional food, and its physicochemical properties and volatile flavor were examined. The contents of chemical compounds showed 5.39% of moisture, 17.3% of total sugars, 8.6% of reducing sugars, 4.5% of crude ash, 3.9% of crude fiber, 10.6% of crude protein and 1.7% of crude fat and that of free sugars was 1.52% of sucrose, 3.98% of fructose, 1.24% of glucose. Among organic acid was 10.2% of citric acid, 6.29% of oxalic acid and 1.94% of malic acid. The highest component of free amino acids was 1,260.3mg of aspartic acid, 1,054.3mg of glutamic acid, respectively. And that of minerals was 38,789ppm of K. A total of 52 volatile flavor components (11 alcohols, 13 acids, 20 carbonyls, 5 hydrocabons, 3 esters) were identified in the Rubus coreanum, respectively. The major volatile flavor components of Rubus coreanum were 3.78% of linalool in alcohols, 14.40% of caproic acid in acids, 2.99% of 2-hydroxy-4-methoxyacetophenone in carbonyls, 1.59% of aromadendrene in hydrocabons and 0.43% of methyl palmitate in esters.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.53-57
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• 1993

The compositions of non-volatile organic acids, mineral, fiber and fatty acids of leaf mustard were investigated. Non-volatile organic acid contents were higher in leaf than in leaf stalk. Of non-volatile organic acids assayed malic acid was the most abundant in both leaf (79.1 mg%) and leaf stalk (46.4mg%), followed by L-ascorbic, oxalic, citric and succinic acids. Mineral contents were also higher in leaf than in leaf stalk. Both leaf and leaf stalk contained calcium most, followed by magnesium, sodium, iron, zinc and copper. It has also been found that leaf mustard contains more iron than any other Cruciferous vegetables reported. The major fatty acid of total lipid was $\alpha$-linolenir acid (63.2% in leaf, 55.3% in leaf stalk). The ratios of polyun-saturated fatty acids to saturated fatty acids (P/S ratio) were 4.1 in leaf and 2.9 in leaf stalk. The content of pectic substances, in terms of alcohol-insoluble solid, of leaf was 9.4% which was 1.4-fold higher than that of leaf stalk. Of pectic substances, hot soluble pectins (HWSP) were present most and followed by sodium hexametaphosphate soluble (HXSP) and HCI soluble pectins (HSP). Total dietary fiber content of mustard leaf was 2.68% and in general, higher content of total dietary fiber than leaf had. Neutral detergent fiber content was higher than acid detergent fiber, and cellulose was higher than hemicellulose by 2.1-fold in leaf stalk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.9
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• pp.1347-1355
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• 2015

In this study, the physicochemical properties, antioxidant capacities, and volatile flavor compounds of oriental melon wine prepared by freeze concentration after heat treatment (HA), ascorbic acid treatment (AAT), and heat and ascorbic acid treatment (HAAT) were investigated. During fermentation period, the melon wine by HAAT showed greater reduction of soluble solids and reducing sugar contents compared to other treatments. In addition, the melon wine treated with HAAT also showed a higher L value and lower browning index compared to other treatments. After aging, free sugar including fructose, and organic acids including citric acid, succinic acid, and malic acid were detected in all samples. For antioxidant activities and contents, HAAT treated wine showed greater antioxidant activities and total phenolic contents than those of others. In GC/MS analysis, a total of 33 volatile flavor compounds were identified. In the principal component analysis of volatile flavor compounds, principal components 1 and 2 represented 88.15% of the whole date distribution and showed opposite tendencies. Taken together, HAAT enhanced the antioxidant activities and sensory properties of oriental melon wine. Moreover, freeze concentration gave the different volatile flavor characteristics in oriental melon wine.