This study investigated the effects of grape seed extract(GSE)on fresh and cooked meat color and premature browning(PMB)in ground meat patties(85% beef and 15% pork back fat)packaged under high-oxygen modified atmosph...This study investigated the effects of grape seed extract(GSE)on fresh and cooked meat color and premature browning(PMB)in ground meat patties(85% beef and 15% pork back fat)packaged under high-oxygen modified atmospheres(HiOx-MAP).The GSE was added to patties at concentrations of 0,0.10,0.25,0.50 and 0.75 g kg^(-1).This study evaluated the surface color,pH,lipid oxidation,and total viable counts(TVC)of raw patties,and the internal color and pH of patties cooked to a temperature of 66 or 71℃ over 10-day storage at 4℃.Compared with the control(0 g kg^(-1) GSE),GSE improved the color stability(P<0.05)and significantly inhibited the lipid and myoglobin oxidation of raw patties from day 5 to 10,but GSE had no effect(P>0.05)on TVC.Patties containing 0.50 and 0.75 g kg^(-1) GSE cooked to 66℃ exhibited greater(P<0.05)interior redness than the control and reduced the PMB of cooked patties in the late storage stage.These results suggested that 0.50 and 0.75 g kg^(-1) GSE can improve fresh meat color and minimize PMB of HiOx-MAP patties.展开更多
Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the ...Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.展开更多
A study was conducted to compare the carcass yield and meat quality of Rutana, Gumuz and Washera sheep of Ethiopia under two concentrate supplement levels (CSL), low (300 g/day) and high (450 g/day). The supplement co...A study was conducted to compare the carcass yield and meat quality of Rutana, Gumuz and Washera sheep of Ethiopia under two concentrate supplement levels (CSL), low (300 g/day) and high (450 g/day). The supplement contains 45% wheat bran, 26% maize grain and 29% Noug cake. A total of 36 sheep (12 from each genotype) were used in 3 × 2 factorial treatment arrangement (3 genotypes and 2 CSL) which was used in a completely randomized block design. Hay was fed ad libitum at a rate of 20% refusal. After the completion of 90 days fattening period, all sheep were slaughtered and meat sample from longissimus dorsi muscle of each animal was taken for sensory evaluation and instrumental measurement of tenderness and for color, pH, and chemical composition analysis. Slaughter body weight (SBW) (26.0 vs. 24.1 kg), hot carcass weight (HCW) (11.3 vs. 9.7 kg), dressing percentage (DP) on SBW (43.4% vs. 40.1%) and EBW basis (53.6% vs. 50.9%), and rib eye-muscle (REM) were higher for the high than low CSL. Rutana sheep had heavier HCW (11.9 kg) than Gumuz (10.1 kg) and Washera (9.4 kg) sheep. DP on EBW basis was higher for Rutana (54.7) than Washera sheep (48.1), while the value for Gumuz (50.9) was similar with both genotypes. Meat from high supplemented sheep had higher fat (9.7% vs. 8.8%), tenderness, juiciness, flavor and lower shear forces than the low level of supplementation. Most sensory parameters measured were in the order of Rutana > Gumuz > Washera sheep. It is concluded that Rutana sheep were relatively more suitable than Gumuz and Washera sheep for production of better carcass yield. The potential of Washera sheep to produce more carcass yield relative to their HCW, SBW and EBW was comparable with that of Gumuz sheep.展开更多
基金supported by the National Natural Science Foundation of China(31871731)the Key Technology Research and Development Program of Shandong,China(2019GNC106050)+1 种基金the China Agriculture Research System of MOF and MARA(CARS-37)the Key Technology Research and Development Program of Binzhou City,China(2019ZDYF010)。
文摘This study investigated the effects of grape seed extract(GSE)on fresh and cooked meat color and premature browning(PMB)in ground meat patties(85% beef and 15% pork back fat)packaged under high-oxygen modified atmospheres(HiOx-MAP).The GSE was added to patties at concentrations of 0,0.10,0.25,0.50 and 0.75 g kg^(-1).This study evaluated the surface color,pH,lipid oxidation,and total viable counts(TVC)of raw patties,and the internal color and pH of patties cooked to a temperature of 66 or 71℃ over 10-day storage at 4℃.Compared with the control(0 g kg^(-1) GSE),GSE improved the color stability(P<0.05)and significantly inhibited the lipid and myoglobin oxidation of raw patties from day 5 to 10,but GSE had no effect(P>0.05)on TVC.Patties containing 0.50 and 0.75 g kg^(-1) GSE cooked to 66℃ exhibited greater(P<0.05)interior redness than the control and reduced the PMB of cooked patties in the late storage stage.These results suggested that 0.50 and 0.75 g kg^(-1) GSE can improve fresh meat color and minimize PMB of HiOx-MAP patties.
基金financed by the National Natural Science Foundation of China(NSFC)(31601978)the China Agriculture Research System-Beijing Team for Poultry Industrythe Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.
文摘A study was conducted to compare the carcass yield and meat quality of Rutana, Gumuz and Washera sheep of Ethiopia under two concentrate supplement levels (CSL), low (300 g/day) and high (450 g/day). The supplement contains 45% wheat bran, 26% maize grain and 29% Noug cake. A total of 36 sheep (12 from each genotype) were used in 3 × 2 factorial treatment arrangement (3 genotypes and 2 CSL) which was used in a completely randomized block design. Hay was fed ad libitum at a rate of 20% refusal. After the completion of 90 days fattening period, all sheep were slaughtered and meat sample from longissimus dorsi muscle of each animal was taken for sensory evaluation and instrumental measurement of tenderness and for color, pH, and chemical composition analysis. Slaughter body weight (SBW) (26.0 vs. 24.1 kg), hot carcass weight (HCW) (11.3 vs. 9.7 kg), dressing percentage (DP) on SBW (43.4% vs. 40.1%) and EBW basis (53.6% vs. 50.9%), and rib eye-muscle (REM) were higher for the high than low CSL. Rutana sheep had heavier HCW (11.9 kg) than Gumuz (10.1 kg) and Washera (9.4 kg) sheep. DP on EBW basis was higher for Rutana (54.7) than Washera sheep (48.1), while the value for Gumuz (50.9) was similar with both genotypes. Meat from high supplemented sheep had higher fat (9.7% vs. 8.8%), tenderness, juiciness, flavor and lower shear forces than the low level of supplementation. Most sensory parameters measured were in the order of Rutana > Gumuz > Washera sheep. It is concluded that Rutana sheep were relatively more suitable than Gumuz and Washera sheep for production of better carcass yield. The potential of Washera sheep to produce more carcass yield relative to their HCW, SBW and EBW was comparable with that of Gumuz sheep.