• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.11
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• pp.1005-1013
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• 2010

This study was conducted to assess the spray control of flash boiling with mixed fuel in consideration of HCCI (Homogeneous Charge Compression Ignition) engine condition. Mixed fuel existing in two phase regions can control the process of mixture formation under low temperature and density by using the spray resulting from flash boiling which is able to induce rapid evaporation of fuel spray as well as the evaporation of high boiling point component. Because HCCI engine injects the fuel early under ambient conditions, it can facilitate the chemical control of ignition combustion and physical control such as breakup and atomization of liquid fuel by flash boiling of mixed fuel which consists of highly ignitable light oil and highly volatile gasoline. This study was conducted by performing video processing after selected composition and molar fraction of the mixed fuel as major parameters and photographed Schlieren image and Mie scattered light corresponding to the flash boiling phenomenon of the fuel spray that was injected inside a constant volume vessel. It was found that flash boiling causes significant changes in the spray structure under relatively low temperature and density. Thus, we analyzed that the flash boiling spray can be used for HCCI combustion by controlling the mixture formation at the early fuel injection timing.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.656-663
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• 2010

In order to improve the consumer acceptance of fragrant yellow hybrids of $Phalaenopsis$ ($Phal.$), crosses between yellow hybrid varieties were made and the obtained hybrids were investigated for horticultural characteristics as well as difference in fragrance patterns. Cross combination of $Phal.$ Brother lawrence and $Phal.$ Brother saragold yielded good seedling population of 500 plants. Segregation was noticed in color density, spot and stripe patterns on yellow color base of petal and also in fragrance. Six lines with multi-branch on flower stalk and strong fragrance flower were finally selected. Volatile fragrance components were compared among $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids by GC/SAW electronic nose. In the derivative pattern of chromatogram and polar derivative pattern of fragrance, similar dominant peaks appeared on retention time 7-9 s and some hybrid lines had two strong peaks on retention time 20-25 s, respectively. Also in polar frequency pattern of fragrance obtained by $VaporPrint^{TM}$ image analysis among parent flowers and hybrids, an identical strong peak near 8 s of retention time was shown. This single fragrance component is considered a key element of fragrance in $Phal.$ Brother lawrence, $Phal.$ Brother saragold and their hybrids. This peak could be used as a marker for the breeding of fragrance in $Phalaenopsis$.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.98-101
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• 1991

To investigate the aroma difference of commercial Korean green tea caused by manufacturing process and harvesting time, analysis of aroma concentrates of steamed green teas(1st tea, 2nd tea) and parched green teas(1st tea, 2nd tea) was accomplished. Steamed green tea, which had a briskness, greenish odor and sweet-floral odor, contained large amounts of terpene alcohols such as linalool, nerolidol, ketones such as cis-jasmone, 2,6,6-trimethyl-2-hydroxycyclohexanone and indole, Parched green tea, which had a slightly greenish odor and floral, roast odor, contained large amounts of terpene alcohols such as linalool, geraniol, aromatic alcohols such as benzylalcohol, phenylethanol and phenol, indole. Almost same tendency of odor component change of 1st tea and 2nd tea differed to harvesting time being observed in steamed tea and parched tea. In 2nd tea of both samples, aliphatic alcohols such as 1-penten-3-ol, cis-2-penten-1-al and two 2, 4-heptadienal(cis, trans and trans, trans) increased remarkably. It seems that these four components effects on the grade of the odor.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.309-314
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• 2007

The physicochemical and sensory characteristics of rice wine, Yakju, made with different additions of red yeast rice (0, 10, 20, 30, and 40%) were investigated. The pH of the rice wine decreased and the total acidity increased with greater additions of red yeast rice. Furthermore, the total sugar content increased and the alcohol content decreased with increasing amounts of red yeast rice. The color L-value diminished and the color a- and b-values increased with increasing amounts of red yeast rice. Among the volatile flavor compounds, esters, aldehydes, alcohols, and acids were the most important aroma-active compounds identified in the rice wine. The sample with the 10% red yeast rice addition had the highest ester content, which is a primary component in fruit fragrance. The highest overall acceptability values in the sensory test for color, flavor, taste, and overall favorite were 5.10, 5.75, 5.15, 4.65, and 4.50, respectively, with the addition of 10% red yeast rice.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.276-282
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• 2007

In this study, attempts were made to develop a garlic juice extraction method that would result in minimum changes in quality. Protopectinase and a mutienzyme containing cellulase, pectinesterase, ${\beta}-glucanase$, etc. were applied to garlic residue after first extraction, and the yields of garlic juice and the flavor component changes of the juices were investigated. Enzyme concentrations of 0.04, 0.08, and 0.12% which were based on pulp weight before extraction were added and allowed to hydrolyze for 30, 60, 90 and 120 min,. respectively. Increase in the garlic juice yield was observed according to the amount of enzyme added and the reaction time until reaching a maximum point. When 0.12% protopectinase was applied to the garlic residue for 90 min, the yield increased by 13.8%. Under the same conditions, when multienzyme was applied to the garlic residue, the yield increased by 14.5%, which was considered the maximum. The flavor compounds decreased when compared with the total GC peak area of garlic juice prepared without enzymes(control). The volatile flavor compounds in garlic juice prepared with 0.12% protopectinase for 60 min decreased by 6%. The free sugars profile of the garlic juice prepared with 0.12% protopectinase for 60 min was similar to that of the control. The type of enzyme used did not affect the free amino acid profile of the garlic juice. These results indicate that the optimum conditions for extraction of garlic juice are hydrolyzing the residue with 0.12% protopectinase for 60 min, extracting garlic juice from the hydrolyzed reside, and then combining the extracted juice with the first extraction.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.2
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• pp.115-121
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• 1989

A comparative slaughter feeding experiment with steer calves weighing 280 kg and a concurrent digestion trial with wether lambs was conducted to study the energy value of rice straw as influenced by ammonia treatment and mixing with alfalfa hay. Steers were ad libitum fed one of nine completely mixed experimental diets: basal (high concentrate); 25 or 50% of untreated rice straw (URS) or ammoniated (plastic covered bales, 4.6% $NH_3$ by weight) rice straw (ARS) proportionately replacing part of the basal; a 50:50 % mixture of URS or ARS and alfalfa replacing a proportion of the basal at 25 and 50%. Digestibility of the nine complete diets (pelleted to prevent sorting) was determined with four ad libitum fed lambs. Ammoniation increased crude protein level (from 3.6 to 10.8%) and in vitro dry matter digestibility of the rice straw by 15%. The improvement in DE, NEm and NEg by ammoniation of rice straw was 20, 52 and 117%, respectively. Ammoniation of rice straw fed as 50% of the diet improved gains over the diet containing 50% URS, but no significant influence on animal performance was observed when rice straw was fed at the 25% level. Each 10% addition of URS to basal diet decreased empty body gain of steers by 116 gram per day compared with a decrease of 70 gram per day when rice straw had been ammoniated. There was no beneficial effect of ammoniation when the roughage component of the diet was a 50:50 mixture of rice straw and alfalfa. Ammoniation of straw and inclusion of alfalfa generally increased the concentration of total volatile fatty acids in rumen fluid. Ammoniation resulted in reduced concentrations of acetic and propionic acid, but increased concentration of butyric acid. Digestibility of URS was improved by mixing with alfalfa. However, alfalfa hay did not influence digestibility of ARS. Diets in which ARS replaced the basal mixture at 25 and 50% had higher NEm and NEg values than comparable URS diets. The same pattern was observed in the straw: alfalfa mixtures, but differences between URS and ARS were significant only for the 50% roughage diets.

• Food Science and Preservation
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• v.12 no.2
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• pp.107-111
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• 2005

We investigated the quality of vaporized liquid of water-boiled pine needle in the aspects of drinking conformity and aroma characteristics. As a result, there was no hazardous component in the assessment for 45 types of ingredients. Especially, inorganic components such as arsenic (As), lead (Pb), mercury (Hg), and cadmium (Cd) which are harmful to human body were not detected. Additionally, we observed that other ingredients were present within the standard level suitable for drinking. The total 34 volatile components of the vaporized liquid of water-boiled pine needle were identified by dynamic head-space method. Fenchol, bomeol $\beta-fenchyl$ alcohol and bomyl acetate were the major volatiles and composed of 6.7, 13.1, 26.6 and $16.2\%$ of total volatiles, respectively. In addition, the alcohols and aldehydes were the prominent ingredients of which the contents showed comparatively high.

• Journal of the Korean Society of Food Culture
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• v.9 no.4
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• pp.395-400
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• 1994

The objective of this study was to investigate the chemical properties of fermented youbsak sauce to use as a source of the flavor and taste enhancement for kimchi preparation. The pH and total acidities of fermented youbsak sauce were not greatly changed during fermentation. The contents of volatile basic nitrogen and amino type nitrogen were gradually increased during one year fermentation, from 63.7 mg% to 224.8 mg% and from 352.5 mg% to 851.7 mg%, respectively. Acid value were increased until 120 days of fermentation and then it was slightly increased up to 44.3. In fatty acids composition, saturated fatty acids were slightly increased during the fermentation, but unsaturated fatty acids were gradually decreased. Palmitic acid was the most abundant fatty acid and followed by oleic acid, palmitoleic acid, myristic acid and eicosapentaenoic acid. The major amino acids in the early stage of fermentation were arginine, glutamic acid, alanine, leucine and valine, while fermentation progress, the amounts of glutamic acid, lysine, phenylalanine increased. Finally, glutamic acid, lysine, phenylalanine, arginine and alanine became the major amino acids after one year fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.11
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• pp.1452-1456
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• 2008

For the effective use of salmon processing by-products, the food components of salmon frame muscle were investigated and compared with those of fillet muscle. The proximate composition of salmon frame muscle was 73.2 g/100 g muscle for the moisture, 76.9 g/100 g dry material for the protein, 15.7 g/100 g dry material for the lipid and 4.1 g/100 g dry material for the ash. pH and volatile basic nitrogen (VBN) content of salmon frame muscle were 6.63 and 16 mg/100 g, respectively. The proximate composition, pH and VBN of salmon frame muscles were similar to those of salmon fillet muscle. The Hunter values of salmon frame muscle were 55.34 for L value, 16.60 for a value, 19.99 for b value and 48.83 for ${\Delta}E$ value, which were different compared to the salmon fillet muscle. The trichloroacetic acid (TCA) soluble-N content of salmon frame muscle was 542 mg/100 g, which was lower than that of salmon fillet muscle. No difference was found in fatty acid composition, total amino acid, calcium, phosphorus contents and sensory evaluation between salmon frame muscle and salmon fillet muscle. These results suggested that muscle from salmon frame could be used as resources for seafood processing.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.761-767
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• 2006

To determine freshness and quality change of chicken products during storage, we manufactured freshness indicator and monitored the surface pH, volatile basic nitrogen (VBN), thiobarbituric acid reacted substance (TBARS), total bacterial counts, electronic nose analysis, and sensory evaluation. All chicken products (drum, wing, thigh) had a change in color of freshness indicator after storage of 3 days at $4^{\circ}C$, indicating poor quality at the time. VBN, TBARS values, and total bacterial counts reached the decay point at the time of color change of freshness indicator attached to the surface of chicken samples. The sensory evaluation also indicated sample was not acceptable by off-odor at day 4 of storage. According to electronic nose analysis to examine off-odor, there were significant differences in terms of principal component analysis values among chicken samples of day 0, day 3, and day 5 of storage. These results suggest that freshness indicator should be useful in determining expiration date of chicken products during marketing by indicating the microbial safety as well as physicochemical and sensory change.