The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Si...The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Sixty-four barrows with an initial body weight of 73.05±2.34 kg were randomly allocated into 1 of 4 dietary treatments in a 2(100%vs.125%NRC CP level)×2(0 vs.300 mg/kg GAA)factorial arrangement(n=7).The feeding trial lasted for 49 d.GAA supplementation significantly reduced drip loss(P=0.01),free water distribution(T23peak area ratio)(P=0.05)and the concentrations of free alanine,threonine,methionine and isoleucine(P<0.05);but increased total glycine content(P=0.03)in the longissimus dorsi muscle of finishing pigs regardless of the dietary CP levels.Furthermore,primary myogenic cell differentiation system was employed to investigate the influence of inclusion of GAA on free amino acid concentrations in myotubes(n=4)and validate the finding in the animal feeding trial.We found that GAA inclusion in culture medium also decreased intracellular concentrations of free alanine,threonine,methionine,isoleucine,valine and proline in differentiated primary myogenic cells in vitro(P<0.05).Meanwhile,relative to diets with 100%NRC CP level,the intake of diets with 125%NRC CP level improved sarcoplasmic protein solubility,increased the contents of carnosine and total free amino acids as well as flavor amino acids in the longissimus dorsi muscle and decreased backfat thickness at the 6-7th ribs in pigs(P<0.05).In addition,we observed that the impact of dietary GAA supplementation on the last rib fat thickness,shear force,and free lysine content in the longissimus dorsi muscle was dependent on dietary CP levels(P<0.05).Collectively,dietary GAA supplementation can reduce drip loss,decrease the concentrations of free amino acids and flavor amino acids of fresh meat independent of dietary CP levels.展开更多
“高蛋白低脂”作为一种新的食品理念备受欢迎。为研究一款以蛋清蛋白颗粒(egg white protein particle,EWPP)为增稠剂的低脂酸奶,该研究通过测定低脂酸奶的pH、质构、流变性等指标,探究EWPP添加对低脂酸奶品质的影响,同时探索了低脂酸...“高蛋白低脂”作为一种新的食品理念备受欢迎。为研究一款以蛋清蛋白颗粒(egg white protein particle,EWPP)为增稠剂的低脂酸奶,该研究通过测定低脂酸奶的pH、质构、流变性等指标,探究EWPP添加对低脂酸奶品质的影响,同时探索了低脂酸奶配方中白砂糖和代糖配比对产品品质的影响。研究发现,EWPP添加后低脂酸奶的pH降低,保水性增加;EWPP在低脂酸奶中表现出良好的吸水性和增稠性。流变学研究发现,含EWPP的低脂酸奶表现出剪切变稀的非牛顿流体特性,EWPP添加量增加后G’显著提高,表观黏度和触变环大小也随着EWPP添加量的增加而提高,说明EWPP的添加有利于低脂酸奶弹性和黏度提升。代糖比例提高对酸奶保水性、质构和黏稠度均有不利影响。感官评定结果发现,添加1%EWPP,m(白砂糖)∶m(代糖)=2∶4的酸奶样品具有最佳的风味、口感和色泽。展开更多
基金financially supported by the National Key R&D Program of China(Grant no.2018YFD0500402)S&T Program of Hebei(199A7310H)。
文摘The current study was carried out to detect the effect of dietary guanidinoacetic acid(GAA)supplementation on carcass characteristics and meat quality in finishing pigs fed different dietary crude protein(CP)levels.Sixty-four barrows with an initial body weight of 73.05±2.34 kg were randomly allocated into 1 of 4 dietary treatments in a 2(100%vs.125%NRC CP level)×2(0 vs.300 mg/kg GAA)factorial arrangement(n=7).The feeding trial lasted for 49 d.GAA supplementation significantly reduced drip loss(P=0.01),free water distribution(T23peak area ratio)(P=0.05)and the concentrations of free alanine,threonine,methionine and isoleucine(P<0.05);but increased total glycine content(P=0.03)in the longissimus dorsi muscle of finishing pigs regardless of the dietary CP levels.Furthermore,primary myogenic cell differentiation system was employed to investigate the influence of inclusion of GAA on free amino acid concentrations in myotubes(n=4)and validate the finding in the animal feeding trial.We found that GAA inclusion in culture medium also decreased intracellular concentrations of free alanine,threonine,methionine,isoleucine,valine and proline in differentiated primary myogenic cells in vitro(P<0.05).Meanwhile,relative to diets with 100%NRC CP level,the intake of diets with 125%NRC CP level improved sarcoplasmic protein solubility,increased the contents of carnosine and total free amino acids as well as flavor amino acids in the longissimus dorsi muscle and decreased backfat thickness at the 6-7th ribs in pigs(P<0.05).In addition,we observed that the impact of dietary GAA supplementation on the last rib fat thickness,shear force,and free lysine content in the longissimus dorsi muscle was dependent on dietary CP levels(P<0.05).Collectively,dietary GAA supplementation can reduce drip loss,decrease the concentrations of free amino acids and flavor amino acids of fresh meat independent of dietary CP levels.
文摘“高蛋白低脂”作为一种新的食品理念备受欢迎。为研究一款以蛋清蛋白颗粒(egg white protein particle,EWPP)为增稠剂的低脂酸奶,该研究通过测定低脂酸奶的pH、质构、流变性等指标,探究EWPP添加对低脂酸奶品质的影响,同时探索了低脂酸奶配方中白砂糖和代糖配比对产品品质的影响。研究发现,EWPP添加后低脂酸奶的pH降低,保水性增加;EWPP在低脂酸奶中表现出良好的吸水性和增稠性。流变学研究发现,含EWPP的低脂酸奶表现出剪切变稀的非牛顿流体特性,EWPP添加量增加后G’显著提高,表观黏度和触变环大小也随着EWPP添加量的增加而提高,说明EWPP的添加有利于低脂酸奶弹性和黏度提升。代糖比例提高对酸奶保水性、质构和黏稠度均有不利影响。感官评定结果发现,添加1%EWPP,m(白砂糖)∶m(代糖)=2∶4的酸奶样品具有最佳的风味、口感和色泽。