• Environmental Engineering Research
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• v.8 no.5
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• pp.252-258
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• 2003

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.12
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• pp.1795-1798
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• 2003

Fecal malodor is an acute environmental issue to be solved for the intensive animal agriculture in Japan. Among these substances volatile sulfur such as hydrogen sulfide (HS), methanethiol, and dimethyl sulfide, and dimethyl disulfide are the ones most strictly controlled in the Japanese national regulations. In this experiment, we have screened a range of standard strains of chemoheterotrophic bacteria and of the presently isolated soil bacteria for their capacity to decompose HS. We have demonstrated that Comamonas testosteroni $JCM5832^T$ and our isolate Bacillus sp. had a potential to reduce malodor when applied to the pig feces.

• Food Science and Preservation
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• v.7 no.1
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• pp.33-37
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• 2000

Effects on keeping quality according to the different package environment in cabbage and brccoli were studied. Opened 2 mil LDPE (low density polyethylene) sealed 4 mil LDPE and BA(barrier polyethylene) were used as package films. Weight loss was markedly in opened 2 mil LDPE in cabbage and broccoli as 6 and 28%, respectively. Carbon dioxide was higher in seal-packaging cabbage and broccoli with BA held at 4 $^{\circ}C$ was above 15 and 31% within 15 days, respectively, while oxygen content was depleted to 2% or less after 10 days. The main difference between volatile sulfur-containing compounds produced from cabbage and broccoli were the relative quantities and rates of production of hydrogen sulfide, carbonyl sulfide, methanethiol and dimethyl disulfide in opened 2 mil LDPE , sealed 4 mil LDPE and barrier bags during storage.

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.61-66
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• 1987

2,4,6-Triamino-5-nitrosopyrimidine was prepared using malononitrile and guanidine carbonate, and acetylated refluxing in acetic acid with acetic anhydride in order to activate the nitroso group for nucleophilic attack. Nucleophilic attack of phenylpyrimidium bromide on the nitroso group of 2,4,6-triacetamido-5-nitrosopyrimidine gave the intermediate, which lost pyrdidine to give the nitrone derivative. Addition of the methanethiol anion to nitrone gave 2,4-diacetamido-7-phenyl-6-methylthiopteridine which was hydrolyzed to give 2,4-diamino-7-phenyl-6-methylthiopteridine. Spectral data (IR, M.S, NMR) were provided to identify the reaction products during synthesis.

• Korean Journal of Food Science and Technology
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• v.36 no.1
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• pp.1-8
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• 2004

Effects of temperature, discoloration, and conditioning on garlic compositions before and after storage were examined. Proximate composition, soluble solids, pH, organic acids, and total sugars of all samples were not significantly different. Sugar contents were sucrose > fructose > glucose, and included such fructooligosaccharide as 1-kestose, 1-nystose, and 1-F-fructosyl nystose. Allicin contents in control, green discolored, and conditioned garlics were 647,9, 613.8, and 648.0 mg%, respectively. Thirty-two flavor compounds were identified by GC/MSD, including 11 sulfide compounds, 5 acids, and 3 aldehydes. Contents of sulfur compounds, including disulfide(di-propenyl), 2-thiophene methanethiol, thiophene, 3,4 dihydro-3-vinyl-1,2-dithiin, and 2-vinyl-4H-1,3-dithin, and water-soluble pectins in low temperature-stored garlic were higher than those in control, and decreased by conditioning or inducing green discoloration. These results show sulfur compounds and water-soluble pectins accumulated in low temperature stored-garlic, and are then converted into green pigments by alliinase in disintegrated garlic tissues.

• Food Engineering Progress
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• v.13 no.3
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• pp.190-194
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• 2009

The aim of this study was to investigate the change of volatile aroma compounds in kimchi during fermentation, before and after drying process. Also, the encapsulation effect of cyclodextrin on volatiles during the drying process was examined. GC-MS was used for detection and identification of volatile compounds. During kimchi fermentation, in the early stage, dimethyl sulfide, carbon disulfide were detected as major compounds and after 7 days several sulfur compounds, dimethyl disulfide, methyl 2-propenyl disulfide, allyl methyl sulfide, and di-2-propenyl disulfide bacame the major volatiles. After vacuum-drying, the kimchi powder lost 11 compounds but still retained 13 volatiles of which major compounds were dimethyl sulfide, acetaldehyde and methanethiol. In order to keep volatiles in kimchi powder along with the drying process, 0.25-1.0% cyclodextrin was added in kimchi and dried-kimchi was prepared by using vacuum dryer. Cyclodextrin acted as an encapsulation agent for aroma compounds and it resulted in less loss of volatiles during drying process. Addition of cyclodextrin will permit industry-scale production of dried-kimchi powder with less loss of aroma compounds.

• Journal of Food Hygiene and Safety
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• v.36 no.6
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• pp.537-545
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• 2021

This study investigated the characteristics of taste and flavor in various wintering-radish extracts using electronic sensors. Sourness showed the highest sensor value (6.9) in hot brewed extracts of white radish part. Saltiness showed the highest sensor value (8.0) in cold brewed extracts of green radish part. Umami showed the highest sensor value (8.3) in hot brewed extracts of white radish part. Sweetness showed the highest sensor value (6.8) in cold brewed extracts of green radish part. Bitterness showed the highest sensor value (7.5) in espresso extracts of green radish part. A total of 16 volatiles were identified using electronic nose. Among these volatile compounds in radish extracts, methanethiol was found to be the predominant volatile compound. These sensory characteristics in radish extracts can be used as basic research data in the food industry.

• Asian Journal of Atmospheric Environment
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• v.11 no.1
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• pp.15-28
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• 2017

The adsorptive removal properties of synthetic A4 zeolite were investigated against a total of 16 offensive odors consisting of reduced sulfur compounds (RSCs), nitrogenous compounds (NCs), volatile fatty acids (VFAs), and phenols/indoles (PnI). Removal of these odors was measured using a laboratory-scale impinger-based adsorption setup containing 25 g of the zeolite bed (flow rate of $100mL\;min^{-1}$). The high est and lowest breakthrough (%) values were shown for PnIs and RSCs, respectively, and the maximum and minimum adsorption capacity (${\mu}g\;g^{-1}$) of the zeolite was observed for the RSCs (range of 0.77-3.4) and PnIs (0.06-0.104), respectively. As a result of sorptive removal by zeolite, a reduction in odor strength, measured as odor intensity (OI), was recorded from the minimum of approximately 0.7 OI units (indole [from 2.4 to 1.6]), skatole [2.2 to 1.4], and p-cresol [5.1 to 4.4]) to the maximum of approximately 4 OI units (methanethiol [11.4 to 7.5], n-valeric acid [10.4 to 6.5], i-butyric acid [7.9 to 4.4], and propionic acid [7.2 to 3.7]). Likewise, when removal was examined in terms of odor activity value (OAV), the extent of reduction was significant (i.e., 1000-fold) in the increasing order of amy acetate, i-butyric acid, phenol, propionic acid, and ammonia.

• Food Science of Animal Resources
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• v.42 no.4
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• pp.593-608
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• 2022

The effect of hot-air dried Lentinula edodes pileus (DLE) on the quality and organoleptic properties of rolled-dumplings was evaluated. DLE was prepared by drying at 60℃ for 24 h and added (Non, 7%, and 9%) to rolled-dumplings. The proximate composition, pH, color (CIE L^*, a^*, b^*), and cooking yield were analyzed. Texture profile analysis, electronic-nose (e-nose), electronic-tongue (e-tongue), and organoleptic evaluation were also conducted. The cooking yield of dumplings with 9% DLE was significantly lower than that of the congeners without DLE, whereas 7% DLE did not lead to significant differences compared without DLE. With increasing DLE addition, the pH and lightness of the dumplings decreased significantly, whereas the redness tended to increase. The texture profile was significantly higher for the dumplings with DLE compared to those without DLE. E-nose analysis confirmed that DLE addition led to the positive odors (methanethiol: meaty, sulfurous; 3-methylbutanal: malty, toasted) and the negative odors (trimethylamine: ammoniacal; acetic acid: acidic, sour). E-tongue analysis showed that DLE addition decreased the intensity of the sourness and increased the intensity of the saltiness and umami of rolled-dumplings. DLE addition improved the overall organoleptic properties, but 9% DLE can be recognized as a foreign substance in organoleptic acceptance. Consequently, DLE has the potential to serve as a flavor and odor enhancer for rolled-dumplings, and the addition of DLE can positively improve consumer acceptance by improving the quality and organoleptic properties.

• Journal of Ginseng Research
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• v.40 no.4
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• pp.315-324
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• 2016

Background: Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. Methods: In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. Results: The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P. notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. Conclusion: The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.