Wang X, Parsons C M
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
Poult Sci. 1998 Jun;77(6):834-41. doi: 10.1093/ps/77.6.834.
Experiments were conducted to evaluate amino acid digestibility of 32 commercial meat and bone meals (MBM) varying in raw material source and produced in seven different commercial cooking systems and at two processing temperatures (low vs high) that differed by 15 to 20 C. Raw material sources included all beef, all pork, mixed species, and high bone MBM. True digestibilities of amino acids were determined using the precision-fed cecectomized rooster assay. Protein efficiency ratio (PER) of six MBM varying greatly in amino acid digestibility was determined with chicks fed 10% CP diets containing a MBM as the sole source of dietary protein. The 32 MBM samples averaged 53.2% CP, 2.73% Lys, 0.6% Cys, and 0.75% Met on a DM basis. True digestibility averaged 82% for Lys, 87% for Met, and 47% for Cys. True digestibilities of amino acids varied substantially among processing systems and temperatures, particularly for Lys and Cys. For example, Lys and Cys digestibility ranged from 68 to 92% and from 20 to 71%, respectively, among different MBM. The higher processing temperature generally yielded lower amino acid digestibility than did the low processing temperature. A smaller, less consistent, effect was observed for raw material source. The PER values of the six selected MBM varied from 0.97 to 2.68 and were highly correlated with amino acid digestibility. These results indicated that very high amino acid digestibility MBM can be produced in commercial rendering systems. However, differences in processing systems and temperatures can cause substantial variability in amino acid digestibilities.
开展了实验，以评估32种商业肉骨粉（MBM）的氨基酸消化率，这些肉骨粉的原料来源不同，由七种不同的商业烹饪系统生产，且处于两个相差15至20摄氏度的加工温度（低温与高温）下。原料来源包括全牛肉、全猪肉、混合物种以及高骨含量的肉骨粉。使用精确饲喂的切除盲肠公鸡试验测定氨基酸的真消化率。用饲喂含一种肉骨粉作为膳食蛋白质唯一来源的10%粗蛋白日粮的雏鸡，测定了六种氨基酸消化率差异很大的肉骨粉的蛋白质效率比（PER）。以干物质计，32个肉骨粉样品的粗蛋白平均含量为53.2%，赖氨酸含量为2.73%，半胱氨酸含量为0.6%，蛋氨酸含量为0.75%。赖氨酸的真消化率平均为82%，蛋氨酸为87%，半胱氨酸为47%。氨基酸的真消化率在不同加工系统和温度之间差异很大，尤其是赖氨酸和半胱氨酸。例如，不同肉骨粉中赖氨酸和半胱氨酸的消化率分别在68%至92%和20%至71%之间。较高的加工温度通常比较低的加工温度产生更低的氨基酸消化率。对于原料来源，观察到的影响较小且不太一致。六种选定肉骨粉的蛋白质效率比值在0.97至2.68之间，并且与氨基酸消化率高度相关。这些结果表明，在商业提炼系统中可以生产出氨基酸消化率非常高的肉骨粉。然而，加工系统和温度的差异会导致氨基酸消化率出现很大差异。
