• Title/Summary/Keyword: Main compounds

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Wine quality grading by near infrared spectroscopy.

  • Dambergs, Robert G.;Kambouris, Ambrosias;Schumacher, Nathan;Francis, I. Leigh;Esler, Michael B.;Gishen, Mark
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1253-1253
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    • 2001
  • The ability to accurately assess wine quality is important during the wine making process, particularly when allocating batches of wines to styles determined by consumer requirements. Grape payments are often determined by the quality category of the wine that is produced from them. Wine quality, in terms of sensory characteristics, is normally a subjective measure, performed by experienced winemakers, wine competition judges or winetasting panellists. By nature, such assessments can be biased by individual preferences and may be subject to day-to-day variation. Taste and aroma compounds are often present in concentrations below the detection limit of near infrared (NIR) spectroscopy but the more abundant organic compounds offer potential for objective quality grading by this technique. Samples were drawn from one of Australia's major wine shows and from BRL Hardy's post-vintage wine quality allocation tastings. The samples were scanned in transmission mode with a FOSS NIR Systems 6500, over the wavelength range 400-2500 ㎚. Data analysis was performed with the Vision chemometrics package. With samples from the allocation tastings, the best correlations between NIR spectra and tasting data were obtained with dry red wines. These calibrations used loadings in the wavelengths related to anthocyanins, ethanol and possibly tannins. Anthocyanins are a group of compounds responsible for colour in red wines - restricting the wavelengths to those relating to anthocyanins produced calibrations of similar accuracy to those using the full wavelength range. This was particularly marked with Merlot, a variety that tends to have relatively lower anthocyanin levels than Cabernet Sauvignon and Shiraz. For dry white wines, calibrations appeared to be more dependent on ethanol characteristics of the spectrum, implying that quality correlated with fruit maturity. The correlations between NIR spectra and sensory data obtained using the wine show samples were less significant in general. This may be related to the fact that within most classes in the show, the samples may span vintages, glowing areas and winemaking styles, even though they may be made from only one grape variety. For dry red wines, the best calibrations were obtained with a class of Pinot Noir - a variety that tends to be produced in limited areas in Australia and would represent the least matrix variation. Good correlations were obtained with a tawny port class - these wines are sweet, fortified wines, that are aged for long periods in wooden barrels. During the ageing process Maillard browning compounds are formed and the water is lost through the barrels in preference to ethanol, producing “concentrated” darkly coloured wines with high alcohol content. These calibrations indicated heaviest loadings in the water regions of the spectrum, suggesting that “concentration” of the wines was important, whilst the visible and alcohol regions of the spectrum also featured as important factors. NIR calibrations based on sensory scores will always be difficult to obtain due to variation between individual winetasters. Nevertheless, these results warrant further investigation and may provide valuable Insight into the main parameters affecting wine quality.

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Taste Compounds of Fresh-Water Fishes 8. Taste Compounds of Crucian Carp Meat (담수어의 정미성분에 관한 연구 8. 붕어의 정미성분)

  • YANG Syng-Taek;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.3
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    • pp.170-176
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    • 1984
  • This study was directed to define the taste compounds of crucian carp, Carassius caressius, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals in the extracts of crucian carp were analyzed, and then followed by sensory evaluation of synthetic extracts prepared from 44 pure chemicals on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, histidine was dominant occupying $46\%$ of the total free amino acids. The other abundant free amino acids were glycine, lysine, alanine and taurine. As for the nucleotides, IMP was dominant showing about $80\%$ of the total of nucleotides. The most abundant organic base was total creatinine. The content of betaine was poor and TMAO were trace in content. The main organic acids were succinic, propionic, butyric and valeric acid. Small amount of glucose, fructose and inositol were detected and ribose and arabinose were trace in content $K^+,\;Na^+,\;PO_4^{3-}\;and\;Cl^-$ were found to be the major ions and small amount of $Ca^{++}\;and\;Mg^{2+}$ were deleted. Judging from the results of omission test, the major components which contribute to produce the taste were serine, glutamic acid, lysine, arginine, tyrosine, phenylalanine, IMP, $Na^+,\;K^+\;and\;PO_4^{3-}$.

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Taste Compounds of Fresh-Water Fishes 7. Taste Compounds of Wild Eel Meat (담수어의 정미성분에 관한 연구 7. 천연산 뱀장어의 정미성분)

  • YANG Syng-Taek;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.17 no.1
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    • pp.33-39
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    • 1984
  • In order to elucidate the taste compounds of wild eel, Anguilla japonica, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals were analyzed, and then followed by organoleptic test of synthetic extract prepared on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in profile were assessed. In free amino acid composition, lysine was dominant occupying $25\%$ of total free amino acid. The other abundant amino acids were glycine, arginine, alanine and histidine. From the results of analysis of nucleotides, IMP was dominant showing about $70\%$ of total nucleotides while ATP, ADP, AMP, inosine and hypoxanthine were low in content. Among organic bases total creatinine was abundant. The amount of betaine was 24 mg/100 g. The main organic acid were butyric acid, valeric acid and succinic acid. As for the sugars, glucose and inositol were 1-2 mg/ 100g in content. $K^+,\;Na^+,\;PO_{4}^{3-}\;and\;Cl^-$ were found to be the major ions. From the results of omission test the major components which contribute to produce the taste were glycine, serine, glutamic acid, IMP, $Na^+,\;K^+,\;Cl^-,\;PO_{4}^{3-}$, lysine, alanine, isoleucine, aspartic acid and creatinine.

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Treatment and Effect of Sanitizers and Disinfectants in Animal Food Manufacturing Plant (축산물가공공장 살균소독제 처리 및 효과 평가)

  • Yeon, Ji-Hye;Kim, Il-Jin;Park, Ki-Hwan;Park, Byung-Kyu;Park, Hee-Kyung;Park, Dae-Woo;Kim, Yong-Su;Kim, Hyung-Il;Jeon, Dae-Hoon;Lee, Young-Ja;Ha, Sang-Do
    • Korean Journal of Food Science and Technology
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    • v.38 no.4
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    • pp.599-603
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    • 2006
  • This study investigated the efficacy of common sanitizers and disinfectants on E. coli, Staphylococcus aureus, Listeria monocytogenes and Salmonella Typhimurium spiked on the surface of the main processing machine. All four microorganisms were greatly reduced by hydrogen peroxide (1,100 ppm), iodophors (25 ppm) and quarternary ammonium compounds (200 ppm). The reduction levels of E. coli, S. aureus, S. Typhimurium, and L. monocytogenes were 3.5, 3.4, 3.0, and 2.8 $log_{10}CFU/100cm^2$, respectively. Peroxy compounds and quaternary ammonium compounds can be applied to animal food manufacturing plants as a good sanitizer.

Magnetism of Amorphous Bulk $(Sm_{1-x}Pr_x)Fe_2$ Alloys in a Low Magnetic Field (저자장에서 비정질 후막$(Sm_{1-x}Pr_x)Fe_2$의 자성)

  • Kim, Jai-Young
    • Korean Journal of Materials Research
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    • v.5 no.8
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    • pp.913-920
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    • 1995
  • RFe$_2$(R=rare earth) Laves Phase intermetallic compounds are one of the promising materials for magnetostrictive applications, due to large magnetostriction coefficients in the order of 10$^{-3}$ . However, because RFe$_2$intermetallic compounds have large magnetostriction constants as well as large magnetocrystalline anisotropy constants, a large external magnetic field is necessary to reach saturation magnetostriction. Hence researches on giant magnetostriction have been concentrated on producing materials exhibiting a high value of magnetostriction in a low magentic field. The main research trend of the giant magnetostriction to obtain the large value in the low magnetic filed, fortunately as the signs of magnetocrystalline anisotropy constans in RFe$_2$intermetallic compounds alternate with the rare earth metals, has been to substitute the rare earth metal for others and hence to reduce the magnetocrystalline anisotropy energy. In addition, amorphous RFe$_2$alloys have been researched. In this research, both of the methods which are substitution of the rare earth metal and amorphization in RFe$_2$ intermetallic compounds are simultaneously conducted to obtain the large magnetostriction coefficient in the low external magnetic field. Among them, SmFe$_2$and PrFe$_2$are selected, and amorphized in substrate-free bulk state. Magnetism in amorphous bulk (Sm$_{1-x}$ Pr$_{x}$) Fe$_2$alloys is investigated in the low magnetic field.ld.

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Taste Compounds of Fresh-Water Fishes 6. Taste Compounds of Korean Catfish Meat (담수어의 정미성분에 관한 연구 6. 메기의 정미성분)

  • YANG Syng-Taek;LEE Eung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.16 no.3
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    • pp.202-210
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    • 1983
  • In order to elucidate the taste compounds of Korean catfish, Parasilurus asotus, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals in the extracts of Korean catfish were analyzed, and then evaluated by sensory test of synthetic extract prepared on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, glycine was dominant occupying $25\%$ of total free amino acids. The other abundant free amino acids were lysine, taurine and alanine. Judging from the result of analysis of nucleotides, IMP was dominant showing about $70\%$ of total nucleotides while ATP, ADP, AMP, inosine and hypoxanthine were low in content. Among organic bases, total creatinine was abundant and its nitrogen content occupied more than $50\%$ of the total extractive nitrogen. The amount of betaine was 18mg/100g and trace amount of trimethylamine and trimethylamine oxide were detected. The main organic acids were succinic, butyric, propionic and valeric acid. On the other hand, oxalic, fumaric, maleic, tartaric and citric acids were analyzed in trace. As for the sugars, glucose was found to be the most abundant monosaccharide. Extremely small amounts of fructoae, inositol were also detected and ribose and arabinose were trace in content. $K^+,\;Na^+,\;PO_{4}^{3-}$ and $Cl^-$ were found to be the major ions and small amount of $Ca^{2+}$ were defected. The synthetic extract, prepared with about 40 pure chemicals based on the analytical data satisfactorily revealed the natural taste of the original extract except slight difference in meaty taste and mildness. From the results of omission test the major components which contribute to produce the taste were serine, IMP, succinic acid and $PO_{4}^{3-}$.

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Constituents of Antimutagenic Factor from Brown Rice (현미의 항돌연변이 활성물질의 구성성분)

  • Chun, Hyang-Sook;Moon, Tae-Wha;Kim, In-Ho
    • Applied Biological Chemistry
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    • v.38 no.5
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    • pp.478-483
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    • 1995
  • To investigate the constituents of antimutagenic factor from brown rice, methanol extracts were fractionated into ether, ethylacetate, buthanol and aqueous fractions. The ether fractions showed distinct antimutagenic effect and active spot were selected by silica gel chromatography. The specific activity of active spot decreased with isolation of the active components from the methanol extract. Qualitative analyses of the active spot by using various spraying reagents revealed that ninhydrin and orcinol did not develop colored reactions. But, ferric chloride, 2,7-dichlorofluorescein, antimony pentachloride, phosphomolybdic acid, bromothymol blue and rhodamine 6G led to colored reactions. These results suggested that the consitituents of active material were neither polar nor nitrogen-containing compounds and that they may contain phenolic compounds and fatty acid derivatives. Main compounds of the active spot were analyzed to be o-hydroxy benzyl alcohol(saligenin), octanoic acid(caprylic acid), 9,12-cis-octadecadienoic acid(linoleic acid), 11-cis-octadecenoic acid(oleic acid), hexadecanoic acid(palmitic acid), 1H-indole-2-carboxylic acid and 1,2-benzenedicarboxylic acid(phthalate) in GC/Mass spectrum, and antimutagenicity of these active compounds using standard regeant was reconfirmed in S. typhimurium reversion assay.

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Study on the Characteristics of Odor Emitted from Swine Facilities (양돈시설에서 발생하는 악취특성에 관한 연구)

  • Kim, Jae Hyuck;Yoo, Kyung Seun;Oh, Je Beom;Jung, Ju Young
    • Journal of Korean Society of Environmental Engineers
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    • v.34 no.7
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    • pp.439-444
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    • 2012
  • We studied the characteristics of odor emitted from 40 swine facilities across the country under various conditions like rearing densities, management style, ventilation system and swine manure handling characteristics, based on the olfactory and analytical evaluation. Odor concentrations (D/T) measured from swine facilities were respectively an average 4,055 D/T at liquid manure storage tanks on aeration, an average 913 D/T at slurry manure storage, an average 506 D/T at finishing swine facilities and an average 201 D/T at composting facilities. The higher rearing densities and slurry accumulation volume in finishing swine house, the more odor concentration (D/T) was increased. But The odor concentration (D/T) in finishing swine house did not show significant difference according to application of microbial additives. 9 odor compounds ($NH_3$, $H_2S$, MM, DMS, DMDS, PA, n-BA, n-VA, i-VA) were detected at swine facilities and the main odor compounds were volatile sulfur compounds such as $H_2S$, MM and volatile fatty acids compounds such as n-BA, n-VA, i-VA. 97.5% of swine farms surveyed in this study is located within 300 m of residential area and it is easy to bring odor complaints.

Effect of Seaweeds and Adsorbents on Volatile Flavor Components of Onion Juice (해조류 및 흡착제의 첨가가 양파즙의 냄새에 미치는 영향)

  • Kee, Hae-Jin;Park, Yang-Kyun
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1477-1483
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    • 1999
  • In order to retain or remove the flavor components of onions, this study was performed to investigate the effect of seaweeds and adsorbents on volatile flavor components of onion juice by testing a sensory evaluation, measuring the amount of pyruvate and thiosulfinate, and investigating the changes of volatile components by SPME/GC. The main flavor compounds in raw onion juice were dipropyl tetrasulfide, 1-propenyl propyl trisulfide, methyl propyl trisulfide, dipropyl trisulfide. Volatile flavor compounds in onion juice treated with tangleweed, brown-seaweed, laver and celite showed a relatively decreasing tendency compared to untreated onion juice, but most of volatile flavor compounds in onion juice treated with activated charcoal and ${\beta}-cyclodextrin$ were removed. The result of the sensory evaluation with various materials for masking onion flavor showed a significant difference at the p<0.05 level. The amount of pyruvate and thiosulfinate treated with tangleweed, brown-seaweed, laver and celite showed little difference compared to untreated onion juice, but the amount of pyruvate and thiosulfinate treated with activated charcoal and ${\beta}-cyclodextrin$ decreased largely compared to untreated onion juice. As a result of the study, onion juice treated with tangleweed, brown-seaweed, laver and celite showed the effect of preserving the pungent taste and masking the onion flavor. Activated charcoal and ${\beta}-cyclodextrin$added to onion juice might have a role in removing the onion flavor by adsorbing volatile flavor compounds in onion.

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Quality Characteristics and Flavor Compounds of Geumsan Perilla Leaves Cultivated in Greenhouse and Field (온실재배와 노지재배한 금산 깻잎의 품질 특성과 향기성분)

  • 현광욱;구교철;장정호;이재곤;김미리;이종수
    • Food Science and Preservation
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    • v.11 no.1
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    • pp.28-33
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    • 2004
  • Quality and flavor compounds of perilla loaves cultivated in greenhouse(May) and field (August) in Geumsan province were investigated and compared. All perilla leaves contained 4.0% crude protein and 0.8% crude lipid. Crude flavonoid contents of perilla leaves cultivated in greenhouse and field showed 25.2% and 26.5%, respectively and each crude saponin content was 2.7% and 2.8%. Pretense activity were showed 11.8 unit in ethanol extracts and 7.1 unit in water extracts of perilla leaves cultivated in field. Hardness and chewness of bottom parts of field-perilla leaves were higher than those of top and middle part, whereas the cohesiveness of top parts and middle parts of perilla leaves were higher than that of bottom part. Furthermore, texture properties of greenhouse-perilla leaves were similar with those of field-perilla leaves except chewness. Nine kinds of flavor compounds such as 1-octen-3-ol, linalool, ${\beta}$-caryophyllene, ${\alpha}$-caryophylene, ${\alpha}$-farnesene, perilla ketone, nerolidol, eugenol, ${\alpha}$-cadinol were identified in greenhouse-perilla and field-perilla leaves, showing that main flavor compound was perilla ketone.