The extraction conditions were optimized by response surface methodology.Results shows that the optimum conditions are 70% alcohol water solution as extraction solvent,extraction temperature 60℃,the ratio of solvent to defatted rapeseed meal 6.82∶1,washing for six times and 20 minutes once.By this way,the rapeseed protein concentrate reach 62.48% in protein content and is light in color,bland in taste.In the product,glucosinolation can be totally taken off and tanin descended by 90%.
采用分光光度法,研究了铅与meso-四(4-苯基)卟啉(TPP)的配合反应,探讨了加热时间、NaOH用量、Tween-80用量等对配合物的生成及稳定性的影响。确定了反应的最佳条件为:1.4 mL NaOH,1.4 mL TPP,0.8 mL Tween-80,沸水浴中加热20 min。络合物的最大吸收波长为468 nm,当铅含量在0～0.5μg/mL范围时,测得的曲线呈线性关系,服从比尔定律,表观摩尔吸光系数为1.71×105 L/(mol.cm),重复性较好。将该方法用于测定儿童食品中铅的含量,取得了较满意的效果。
