Zhang Y, Parsons C M
Department of Animal Sciences, University of Illinois, Urbana 61801, USA.
Poult Sci. 1996 Apr;75(4):514-8. doi: 10.3382/ps.0750514.
Two experiments were conducted to evaluate the effects of overprocessing by autoclaving on the in vivo protein quality and in vitro protein solubility in 0.2% KOH of solvent-extracted peanut meal containing 48% protein. The peanut meal was autoclaved at 120 C and 105 kPa for 0, 20, 30, 40, 50, 60, or 90 min. In vivo protein quality of the autoclaved peanut meal was evaluated in chicks fed corn-peanut meal diets (22.5% protein) from 8 to 22 d of age and in adult cecectomized roosters using a precision-fed amino acid digestibility assay. Chick performance was significantly decreased when peanut meal had been autoclaved (P < 0.05) 60 min or more in one experiment and by 40 min or more in the other experiment. True digestibility of amino acids in peanut meal also decreased as autoclaving time increased. The effect of autoclaving was greatest for lysine, wherein digestibility was 87, 72, 68, and 57% for peanut meal autoclaved for 0, 30, 60, or 90 min, respectively. Protein solubility of peanut meal in 0.2% KOH decreased from 78 to 56% as autoclaving time increased from 0 to 90 min. Protein solubility values of 70% or lower were indicative of decreased in vivo peanut meal quality. The results of this study indicated that overprocessing by autoclaving reduces the protein quality of peanut meal and that protein solubility in KOH is a useful in vitro index of overprocessing.
进行了两项试验，以评估高压灭菌过度处理对含48%蛋白质的溶剂萃取花生粕的体内蛋白质质量和体外蛋白质在0.2%氢氧化钾中的溶解度的影响。将花生粕在120℃和105千帕下高压灭菌0、20、30、40、50、60或90分钟。用精确饲喂氨基酸消化率测定法，对8至22日龄饲喂玉米-花生粕日粮（蛋白质含量22.5%）的雏鸡和成年切除盲肠的公鸡，评估高压灭菌花生粕的体内蛋白质质量。在一项试验中，花生粕高压灭菌60分钟及以上时，雏鸡性能显著下降（P<0.05）；在另一项试验中，高压灭菌40分钟及以上时，雏鸡性能显著下降。随着高压灭菌时间的增加，花生粕中氨基酸的真消化率也降低。高压灭菌对赖氨酸的影响最大，其中，高压灭菌0、30、60或90分钟的花生粕，其消化率分别为87%、72%、68%和57%。随着高压灭菌时间从0增加到90分钟，花生粕在0.2%氢氧化钾中的蛋白质溶解度从78%降至56%。蛋白质溶解度值低于70%表明花生粕的体内质量下降。本研究结果表明，高压灭菌过度处理会降低花生粕的蛋白质质量，并且蛋白质在氢氧化钾中的溶解度是过度处理的一个有用的体外指标。
