• Korean Journal of Food Science and Technology
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• v.27 no.2
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• pp.241-245
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• 1995

Focusing on quality problems of delayed chilling porcine muscle, the effects of delayed chilling and aging on the contents of ATP-related compounds and taste of pork were investigated. Twelve Landrace pigs were employed and bisected: left sides were delay-chilled(DC) at room temperature($20^{\circ}C$) for 3 hrs, whereas right sides were conventionally chilled(CC). ATP-related compounds tested were adenosine triphosphate(ATP) and its derivatives in pork muscle, inosine monophosphate(IMP), guanosine monophosphate(GMP) and L-glutamate in cooked broth. DC sides showed more rapid pH decline and degradation of nucleotides than did CC sides. The levels of ATP and adenosine monophosphate(AMP) were not changed significantly. However, adenosine diphosphate(ADP) and IMP showed the highest levels at the 1st and 5th day, respectively. Hypoxanthine(Hx) was gradually increased(p<0.05) during aging. During aging, the IMP contents cooked broth tended to decrease, while the GMP and L-glutamate contents increase. As a result of these, the taste score got better and finally the results of sensory evaluation became increased(p<0.05). However, compared to CC sides, DC sides did not seem to lower taste of pork.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.246-249
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• 1994

Shelf-life of pork packaged under $CO_{2}$ was observed and the optimal volume of $CO_{2}$ gas was determined. High gas barrier film, EVOH($CO_{2}$ permiability; 1 $cc/cm^{2}{\cdot}24\;h{\cdot}atm$) was used as packaging material and the volume ratios of sample to $CO_{2}$ of 1 : 1, 1 : 3 and 1 : 5 were tried using the control of vacuum packaged pork. To ev.3luate quality of pork cuts, total plate counts, TBA, color and sensory score were monitored during the storage at $4{\pm}1^{\circ}C$ for 31 days. TPC of vacuum packaged pork increased up to $4.6{\times}10^{6}\;CFU/cm^{2}$ in 24 days while that of $CO_{2}$ gas packaged pork $4.5{\times}10^{5}\;CFU/cm^{2}$ at the same storage period, and it took 7 days more for gas packaged pork to reach the same TPC count. There was no significant difference in TBA value between vacuum packaged and gas packaged pork. In the color L and a values were not affected by treatment but vacuum packaged pork cuts showed higher b value than gas packaged pork. According to sensory evaluation, gas packaged pork showed less off flavor, better flavor and freshness than vacuum packaged one (P<0.05).

• Korean journal of food and cookery science
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• v.26 no.3
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• pp.307-313
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• 2010

Yogurt base was prepared from skim milk added with 0.5, 1.0 and 1.5% (w/v) black garlic extracts(BGE, 60 brix), fellowed by fermentation with Lactic acid bacteria (the mixed strain of Streptococcus thermophilus, Lactobacillus delbrueckii subsp. bulgaricus) at $42^{\circ}C$ for 24 hr. The yogurt products were evaluated for acid production (pH, titrable acidity), number of viable cells, viscosity, color value, and sensory properties. The pH of yogurt with BGE was below 6.0 at 6 hr fermentation, after which it was rapidly acidifies. Aftert 24 hr, the titratable acidity of yogurt with 1.5% BGE was 0.74%, which was 5.7 times higher than that before fermentation. There was no significant difference in viable cell count between the samples after 3 hr fermentation. The viscosity of yogurt was decreased by the addition of BGE. As the percentage of BGE increased, the L value (lightness) decreased while the a value (redness) and b value (yellowness) increased. The overall sensory score of yogurt with BGE was lower than that of yogurt with only skim milk. Therefore, moderate addition of BGE was below 1% for the preparation of yogurt.

• Applied Biological Chemistry
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• v.34 no.2
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• pp.149-153
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• 1991

Several commercial soybean oils were stored at $20^{\circ}C,\;40^{\circ}C$ and $60^{\circ}C$ with daily exposure of fluorescent light for 12 hours and evaluated their rancidity by headspace gas chromatographic analysis of pentanal and hexanal. The data of gas chromatographic analysis was compared with organoleptic flavor evaluation. For headspace gas chromatographic analysis, the volatile compounds were recovered by porous polymer trap and flushed into a fused silica capillary column at $250^{\circ}C$, The pentanal and hexanal separated were identified by gas chromatography and gas chromatography-mass spectrometric method. The results showed that the contents of pentanal and hexanal were linearly increased during storage for 100 days. A very simple linear relationship was found between organoleptic flavor scores and amounts of two volatile compounds with very high correlation coefficient. A similar linear relationship was also obtained for acid and peroxide value with sensory data. This results suggested the possible implication of pentanal and hexanal as an quality index for rancidity evaluation of soybean oil.

• Journal of Veterinary Clinics
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• v.27 no.4
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• pp.343-347
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• 2010

The purpose of this study was to determine the antagonistic effects of yohimbine on sedation induced in dogs with medetomidine. Six mixed breed dogs were repeatedly used at a 2 weeks withdrawal time in this study. The dogs received $40\;{\mu}g/kg$ of medetomidine followed 15 minutes later by 0.2 ml/kg saline solution (group M) or 0.11 mg/kg yohimbine (group MY). All the dogs were examined before and 5, 15, 30, 45, 60, 75, 90, 120 and 150 minutes after the injection of medetomidine, and the induction and recovery times, vital signs, blood biochemistry and anesthetic quality were recorded. There were significant differences in the recovery of anesthesia between the groups. In both groups the heart rate decreased rapidly down to five minutes after the administration of medetomidine. The activity of ALT, AST and the protein concentration did not change significantly in either group and there was no significant difference between them at any time. Response to noise, muscle tone and analgesic score in the MY group at 30 minutes were significantly lower than those of the M group. When recovering from anesthesia, the dogs treated with yohimbine took less time to achieve sternal recumbency and less time to be able to stand and walk. It was concluded that yohimbine reversed effectively medetomidine sedation in dogs.

• Journal of Animal Science and Technology
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• v.58 no.6
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• pp.23.1-23.17
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• 2016

Background: The functionality of myofibrillar proteins is a major factor influencing the quality attributes of muscle foods. Nonetheless, the relationships between muscle type and oxidative changes in chevon during ageing are meagrely elucidated. Postmortem changes in antioxidant status and physicochemical properties of glycolytic gluteus medius (GM) and oxidative infraspinatus (IS) muscles in goats were compared. Methods: Twenty Boer bucks (9-10 months old, body weight of $36.9{\pm}0.725kg$) were slaughtered and the carcasses were subjected to chill storage ($4{\pm}0.5^{\circ}C$). Analyses were conducted on GM and IS muscles sampled on 0, 1, 4 and 7 d postmortem. Results: Chill storage did not affect the antioxidant enzyme activities in both muscles. The IS had greater (P < 0.05) superoxide dismutase and catalase activities than GM. Carotenoid and tocopherol contents did not differ between muscles but decreased (P < 0.05) over storage. The IS had higher (P < 0.05) glycogen and ultimate pH and lower (P < 0.05) shear force and cooking loss than GM. The carbonyl content, % metmyoglobin, drip loss and TBARS increased (P <0.05) while free thiol, metmyoglobin reducing activity (MRA), shear force and myoglobin decreased (P < 0.05) over storage. Muscle type had no effect (P > 0.05) on free thiol, MRA and TBARS. The GM had lower (P < 0.05) redness on d 0 and 1 than IS while the IS had greater carbonyl, % metmyoglobin and drip loss than GM on d 7. The reflective density of slow myosin heavy chain (MHC) was higher (P < 0.05) while the density of fast MHC and actin was lower (P < 0.05) in IS than GM. Regardless of muscle type, the density of MHC decreased (P < 0.05) while that of actin was stable over storage. Nonetheless, the degradation of fast and slow MHC was greater (P < 0.05) in IS than GM. Muscle type had no effect (P > 0.05) on consumer preference for flavour, juiciness and overall acceptability. However, IS had higher (P < 0.05) tenderness score than GM on d 1 and 4 postmortem. Intramuscular fat was higher (P< 0.05) in IS compared with GM. Fatty acid composition did not differ between the muscles. However, GM had lower (P < 0.05) n-6/n-3 ratio than IS. The n-3 and n-6 PUFA declined (P < 0.05) while the SFA increased (P < 0.05) over storage. Conclusion: The changes in myofibrillar proteins and physicochemical properties of goat meat during postmortem chill storage are muscle-dependent.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.175-181
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• 1994

Six Korean medicinal herbs, Codonopsis lanceolata Traut (sasam), Platycodon grandiflorium A. De Candolle (gilkyung), Paeonia lactiflora var. trichocarpa Bunge (peony), Angelica gigas Nakai (danggwi), Astragalus membranaceus Bunge (hwangki) and Cnidium officinale Makino (chunkung) were added in brewing Korean traditional rice wine. Fermentation characteristics such as contents of total acid, reducing sugar, total sugar, pH, temperature, and alcohol concentration were investigated every 24 hr during fermentation periods. Changes of fermentation characteristics were remarkable in the initial period $(1{\sim}4\;days)$, slow in the middle $(5{\sim}7\;days)$, and almost unchangeable in the final $(8{\sim}10\;days)$. Total acid content was remarkably increased during the initial period but slowly afterwards. Reducing sugar content, total sugar content, and pH were remarkably decreased during the initial period but slowly afterwards. Alcohol concentrations of medicinal herb rice wines were $0.3{\sim}1.5%$ lower than the traditional wine throughout the fermentation periods. After the final period of 10 days of fermentation, alcohol concentration was observed as 12.6% in wine from sasam, 12.9% from gilkyung, 12.3% from peony, 12.4% from danggwi, 13.4% from hwangki, 12.6% in wine from chunkung, 13.6% in raditional wine respectively. Those differences were expected as the results of differences in various herbs. From the sensory evaluation, the highest score of overall quality was observed in the wine from hwangki, the next from chunkung, sasam, the traditewional wine, gilkyung, danggwi and the last from peony.

• Korean Journal of Food Science and Technology
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• v.40 no.5
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• pp.485-490
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• 2008

In this study, organic tea leaves were characterized with the aim of developing an organic beverage process. The green tea leaves grown using organic farming techniques were collected in Haenam, Korea. Catechins in green tea leaves were extracted by chloroform and ethyl acetate and these were then analyzed quantitatively and qualitatively by HPLC (high pressure liquid chromatography). The color and pH values of the green tea extracts were also measured. The catechin levels of April-harvested, May-harvested and June-harvested, semi-fermented leaves at 0.5% were 66.24, 29.19, 57.11, and 5.27 ${\mu}g/mL$, respectively. Among the detected catechins, the level of (-)-epigallocatechin gallate was the highest while that of (-)-epigallocatechin was not detected. The June-harvested leaves were selected as raw material for development of the green tea beverage, based on the levels of catechins, economic viability and yield of tea extract. As the level of extract increased, the levels of catechins of 0.1, 0.2, 0.5% also increased by 1.5, 11.78 and 41.01 times. From the results of the sensory evaluation of June-harvested leaf-extract, the sensory score of color was the highest in 0.1%, while the flavor and overall quality were the highest in 0.2%.

• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.694-701
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• 2014

This study aimed to investigate the aging of liquor brewed with fermented wine using ipguk (koji) in a jar (JA) and stainless steel container (SC), which are generally used in Korea, and to review the characteristics of the liquors as a function of aging time. The initial alcohol content was 39.8-40.9%, and gradually decreased in the JA and SC as the aging time increased. In the case of fusel alcohols, the n-propanol, isobutanol, and isoamyl alcohol contents did not increase with increasing aging time, in the cases of both JA and SC. The A/B (isoamyl alcohol/isobutyl alcohol) ratio was similar under reduced pressure (RP) and atmospheric pressure (AP), at 1.32-135. The A/P (isoamyl alcohol/n-propanol) and B/P (isobutyl alcohol/n-propanol) ratios were 2.17-2.22 and 1.62-1.68, respectively. During the early stages of distillation, under RP, the isoamyl alcohol content was the greatest, followed by isobutyl alcohol and ethyl palmitate. Under AP, the isoamyl alcohol content was the greatest followed by decanoic acid, ethyl palmitate, and isobutyl alcohol. The highest sensory score under RP, 60 cmHg, was $6.98{\pm}0.28$.

• Journal of Animal Science and Technology
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• v.46 no.6
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• pp.925-936
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• 2004

The present study was carried out to investigate effects of various factors such as sire, bovine leukemia virus(BLV) carrier/non-carrier, parity, calving month and lactation periods on somatic cell count(SCC) and milk components in dairy cows. The animals calved from January 2001 to March 2004. Milk samples were collected every 30 $\pm$ 5 days in milk(DlM), and somatic cell count and milk components were analysed by Somascope MK2/Lactoscope FTIR Bovine Leukemia Virus(BLV) was detected by ELISA method. The lactation periods were divided into five periods; (1) 30DIM, (2) 31 to 6ODIM, (3) 61 to 120DIM, (4) 121 to 180DIM, and (5) more than 180DIM. The level of SCC and milk components in all lactation periods were significantly affected by sire, parity, calving month, lactation period and BLV carrier/non-carrier. The results suggest that BLV carrier/non-carrier analysis in a herd may be necessary if milk quality is low owing to a high SCC. BLV carrier/non-carrier did not affect milk protein content for all lactation periods.