• Title/Summary/Keyword: 단백질 변성

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Effect of Different Stunning Time on Meat Quality of Broiler (육계 도축 시 전기 실신 시간이 육질에 미치는 영향)

  • Chae, H.S.;Ahn, C.N.;Yoo, Y.M.;Ham, J.S.;Jeong, S.G.;Lee, J.M.;Choi, Y.I.
    • Journal of Animal Science and Technology
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    • v.47 no.6
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    • pp.1017-1024
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    • 2005
  • This study was investigated the effect of the length of stunning time on pH, water holding capacity(WHC), cooking loss(CL), meat color and incidence rate of blood spot in broiler carcass. One-hundred and forty broiler chickens were slaughtered by three different length of stunning times(5 sec., 8 sec., 11 sec.) with the same electrical frequency(255Hz) and 50 voltage in a commercial abattoir. The WBS values and cooking loss of breast muscle were increased with increasing the stunning time, while WHC of breast muscle were decreased. Lightness(L* value) and yellowness(b* value) scores of leg muscle and skin stunned with 50V, 255Hz, 8 sec, 11 sec. were higher than those of broilers stunned with 50V, 255Hz, 5sec(P<0.05). But, there was no significant difference in color on breast and wing muscle. In subjective evaluation, frequence of the first grade had a trend of being increased by extending the stunning time. There was only a few cases of PSE chicken with 0.02%, while blood spot was observed at the highest rate for the 5 sec. treatment. TBARS indicated that a longer length of stunning resulted in a higher rate of fat oxidation. This experiment demonstrated that the length of stunning time has a significant effect on meat quality and its stability during chiller storage.

Biostatic activity of Coix lacryma seed extract on Toxoplasma gondii in macrophages (율무씨 수침 추출물이 대식세포내 톡소포자충에 미치는 영향에 관한 실험적 연구)

  • 소진탁;김숙향
    • Parasites, Hosts and Diseases
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    • v.34 no.3
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    • pp.197-206
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    • 1996
  • Water extract of Coix locrvmn seeds (Co-Ex) was separated into several components; dissolved with Tris-Cl buffer and the supernatant (WC 1), ammonium sulfate treatment supernatant (WC2) and the pellet nvc31,9AE column chromatography of WC 1 and the peak portions; WC4, WCS and WC6. Murine peritoneal macrophages in DMEM containing 10% heat-inactivated FCS were infected with tachyzoites of ToxopIQsmc gondii, RH strain, in uifo. By adding modulators such as Co-Ex, WC 1,2,3,4.5,6 and LPS or IFN-γ for 24 hrs . toxoplasmastatic activity of macrophages was examined in relation to nitrite production. Nitrite production of macrophages was enhanced especially in the series of WC2, WC1 and the combination sample (WC1 + WC2 + WC3) by order than other components or fractions (WC4, WC5, WC6) tested . Toxoplasmastatic actions such as percentage of the inacrophages infected by T. gonnii and fold increase of T gondii in macrophages showed retroverse relations with the amount of nitrite production; i.e. as nitric oxide (NO) increased the phagocytic index of macrophages and the fold increase of tachyzoites in macrophages decreased . Nitrite (NO-2) production was increased by adding IFN-γ in all cases together with enhancement of biostatic effects. Through the results obtained, it is speculated that some components other than the non-proteinous and defatted components in Coix lacrwmn seeds may contribute to activate macrophages through induction of NO for the biostatic activity.

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A Study for Perception of Hair Damage Using Friction Coefficient of Human Hair (모발의 마찰계수를 통한 모발 손상 인식 연구)

  • Lim, Byung Tack;Seo, Hong An;Song, Sang-Hun;Son, Seong Kil;Kang, Nae-Gyu
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.3
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    • pp.295-305
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    • 2020
  • Treatment for beauty using oxidizing agents damages hair with inducing structural alteration in cuticle layer, degradation of protein, and loss of lipid. This study connects a frictional coefficient upon the damaged hair by an instrumental test to the texture test by human being, and considered a moisture as a factor of the damage. A friction coefficient has been measured upon the hair with successive treatment of dye, perm, and bleach. The friction coefficient from the hair dye-treated three times was defined with 0.60, where 58% of answerer indicated an initial damage point as the hairs of iteration of dye-treatment increased. Even bleach treated three times results in 0.84 of friction coefficient corresponding to 88% of answerer attributed the hair to an initially damaged hair. In order to figure out a lipid loss in hair for human being to respond damage, a friction coefficient of the hair was controlled by removing 18-methyleicosanoic acid (18-MEA). The initial damage has been recognized by 0.60 of the friction coefficient for the 68% of answerer. Since moisture is the largest portion of the components in hair, moisture analysis has been performed to study a relationship between texture of damage and the friction coefficient from an instrumental evaluation. As an iteration of dye increases, the hair became hydrophilic with smaller contact angle. It is found that a damaged hair by dyeing possessed more than 0.42% of moisture compared to a healthy hair. Finally, it is elucidated that an increase of moisture in hair induced higher adhesive force corresponding to the friction coefficient, and the friction coefficient above 0.6 is attributed to the preception of hair damage.

Effect of Bleeding Time on Meat Quality and Shelf-Life of Broiler (방혈 시간이 닭고기의 품질 및 저장성에 미치는 영향)

  • Chae H. S.;Ahn C. N.;Yoo Y. M.;Ham J. S.;Jeong S. G.;Lee J. M.;Choi Y. I.
    • Korean Journal of Poultry Science
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    • v.32 no.3
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    • pp.187-193
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    • 2005
  • This study was carried out to investigate the effect of the bleeding times(30sec., 90sec., 150sec.) at slaughtering process on meat quality and storage properties of broiler. The redness$(a^{\ast}\;value)$ of skin, wing, leg muscle decreased at high bleeding time(150sec.). However, there was no significant difference in breast muscle. WHC(water holding capacity) of breast muscle decreased from $63.64\%$ at low bleeding time(30sec.) to $61.06\%$ at high bleeding time. TBARS(thiobarbituric acid-reactive substance) values were 0.18 mgMA/kg at the low bleeding time, 0.16 mgMA/kg at the middle bleeding time(90sec.) and 0.21mgMA/kg high bleeding time on 3 days of storage. Total aerobic plate counts(TPC) were $6.25logCFU/cm^2$ at the low bleeding time, $6.25logCFU/cm^2$ at the middle bleeding time and $6.53logCFU/cm^2$ at the high bleeding time. The TPC was increased as the bleeding time increased. In conclusion, meat color of chicken were acceptable when the carcasses were slaughtered at the high bleeding time.

Effect of Gas Mixture Ratio of Modified Atmosphere Packaging on Quality of Chicken Breast (CO2와 N2 혼합 비율에 따른 포장 닭고기 가슴육의 냉장 저장 중 품질 특성)

  • Chae, Hyun-Seok;Na, Jae-Cheon;Choi, Hee-Cheol;Kim, Min-Ji;Bang, Han-Tae;Kang, Hwan-Ku;Kim, Dong-Wook;Suh, Ok-Seok;Ham, Jun-Sang;Jang, Ae-Ra
    • Food Science of Animal Resources
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    • v.31 no.1
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    • pp.100-106
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    • 2011
  • The physicochemical characteristics of chicken breast were determined to identify the optimal ratio of $CO_2$ and $N_2$ to maintain chicken breast quality during cold storage for 6 d. The mixing ratios of $CO_2$ and $N_2$ were 20:80, 40:60, 60:40, and 80:20, respectively. The pH of the chicken breast packed with 80% $CO_2$ and 20% $N_2$ was lower than that of the control on day 1 (p<0.05). The lightness ($L^*$) of the breast increased with increasing $CO_2$ during storage (p<0.05), whereas no difference was found for redness ($a^*$) and yellowness ($b^*$). A lower volatile basic nitrogen level was found for chicken breasts exposed to higher $CO_2$ levels. Furthermore, lipid oxidation of the chicken breast packed with $CO_2$ decreased with increasing $CO_2$ level, and 40% $CO_2$ significantly reduced 2-thiobarbituric acid reactive substances (TBARS) values on days 1 and 6. The total number of microbes was reduced in chicken breast exposed to more than 40% $CO_2$ during storage days 3 and 6 (p<0.05); however, Escherichia coli was not affected by $CO_2$ level. Coliforms of chicken breast were reduced in the 40% $CO_2$ level on storage day 3. Moreover, tray-packed chicken breast exposed to 40% $CO_2$ did not collapse. These results suggest that 40% $CO_2$ and 60% $N_2$ were the optimal conditions for packaging chicken breasts during cold storage.

Quality Characteristics of Low-Salt and -Fat Meatball Added Black Garlic (Allium sativum L.) during Cold Storage (흑마늘 첨가 저염.저지방 미트볼의 냉장저장 중 품질변화)

  • Jin, Sang-Keun;Kim, Il-Suk;Jeong, Jin-Yeon;Kang, Suk-Nam;Yang, Han-Sul
    • Food Science of Animal Resources
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    • v.30 no.6
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    • pp.1031-1037
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    • 2010
  • The effects of black garlic (Allium sativum L.) addition on the quality characteristics of low-fat and low-salt meatballs during cold storage were investigated. Meatballs were divided into five groups: none (control), 0.1% ascorbic acid (T1), 1% black garlic (T2), 2% black garlic (T3), and 3% black garlic (T4). pH and lightness values were lower in the treatment groups than in controls by storage time. pH and lightness values were decreased with increasing addition of black garlic (p<0.05). Addition of black garlic to meatball resulted in significantly higher TBARS values than that of control and T1 at day 1 (p<0.05). However, the addition of black garlic to meatball resulted in significantly lower VBN values than that of control after storage for 14 d. On day 14 or 21, the VBN values of meatball with added black garlic were lower than those of control and decreased with increasing addition of black garlic (p<0.05). Although addition of black garlic produced low acceptance of color scores, the flavor, tenderness, and juiciness of meatball with added black garlic were similar to those of control and T1 (p>0.05). Based on the current results, addition of black garlic could be recommended for preventing protein degradation in low-salt and low-fat meatball. Further, black garlic could be useful to the pork meat product industry as a food additive.

Facile [11C]PIB Synthesis Using an On-cartridge Methylation and Purification Showed Higher Specific Activity than Conventional Method Using Loop and High Performance Liquid Chromatography Purification (Loop와 HPLC Purification 방법보다 더 높은 비방사능을 보여주는 카트리지 Methylation과 Purification을 이용한 손쉬운 [ 11C]PIB 합성)

  • Lee, Yong-Seok;Cho, Yong-Hyun;Lee, Hong-Jae;Lee, Yun-Sang;Jeong, Jae Min
    • The Korean Journal of Nuclear Medicine Technology
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    • v.22 no.2
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    • pp.67-73
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    • 2018
  • $[^{11}C]PIB$ synthesis has been performed by a loop-methylation and HPLC purification in our lab. However, this method is time-consuming and requires complicated systems. Thus, we developed an on-cartridge method which simplified the synthetic procedure and reduced time greatly by removing HPLC purification step. We compared 6 different cartridges and evaluated the $[^{11}C]PIB$ production yields and specific activities. $[^{11}C]MeOTf$ was synthesized by using TRACERlab FXC Pro and was transferred into the cartridge by blowing with helium gas for 3 min. To remove byproducts and impurities, cartridges were washed out by 20 mL of 30% EtOH in 0.5 M $NaH_2PO_4$ solution (pH 5.1) and 10 mL of distilled water. And then, $[^{11}C]PIB$ was eluted by 5 mL of 30% EtOH in 0.5 M $NaH_2PO_4$ into the collecting vial containing 10 mL saline. Among the 6 cartridges, only tC18 environmental cartridge could remove impurities and byproducts from $[^{11}C]PIB$ completely and showed higher specific activity than traditional HPLC purification method. This method took only 8 ~ 9 min from methylation to formulation. For the tC18 environmental cartridge and conventional HPLC loop methods, the radiochemical yields were $12.3{\pm}2.2%$ and $13.9{\pm}4.4%$, respectively, and the molar activities were $420.6{\pm}20.4GBq/{\mu}mol$ (n=3) and $78.7{\pm}39.7GBq/{\mu}mol$ (n=41), respectively. We successfully developed a facile on-cartridge methylation method for $[^{11}C]PIB$ synthesis which enabled the procedure more simple and rapid, and showed higher molar radio-activity than HPLC purification method.