During Tween-assisted aqueous extraction of peanut oil,the simultaneously obtained aqueous phase was rich with peanut protein.With protein purity,residual oil content,protein recovery and Tween 20 content as evaluation indexes,recovery process of peanut protein powder was optimized in this study,intending to receive high-quality peanut protein powder.Alkali salt saponification,hexanes extraction and high speed centrifugation pretreatment were compared.Acid precipitation and ultrafiltration recovery of peanut protein were both investigated.Protein recovery rate was increased significantly at pH 4.5 by optimizing the pH acid precipitation phase.Protein recovery rate decreased and protein purity rose with the increase of washing times.Protein recovery rate decreased significantly,and protein purity leveled off after washing twice.The acid precipitation pH 4.5 and wash times were decided.By combining of alkali salt saponification method with acid precipitation process,the purity of obtained peanut protein powder was 81.28％,residual oil content was 5.18％,and Tween 20 content was 11.11％,and protein recovery was 84.68％.By using 5 kDa ultrafiltration membrane,peanut protein powder purity was 77.35％,residual oil content was 6.14％,Tween 20 content was 6.36％,and protein recovery was 97.45％.Compared with ultrafiltration,peanut protein powder of acid precipitation had high purity and low residual oil content,ultrafiltration had low Tween 20 content but the purity was not high.%利用吐温辅助水剂法提取花生油脂,将同时得到富含花生蛋白的水提液作为研究对象,以蛋白纯度、残油量、蛋白质回收率和吐温20含量为指标,优化花生蛋白粉的回收工艺,旨在获得纯度较高的花生蛋白粉.比较了碱盐皂化、萃取和高速离心3种水提液脱脂处理方法,分别采用酸沉和膜分离回收花生蛋白.pH＜4.0时,随着pH的升高,蛋白质回收率显著提高;pH为4.5时蛋白质回收率达到最大,为93.17％;pH＞5.0时,蛋白质回收率显著降低,最终确定酸沉最佳pH为4.5.随着蛋白沉淀水洗次数的增加,蛋白质回收率下降,但蛋白纯度显著上升,最终确定水洗蛋白沉淀2次.碱盐皂化、萃取和高速离心3种方法均可降低水提液油脂含量,而采用碱盐皂化法处理水提液结合酸沉工艺,得到的花生蛋白粉纯度最高为8l.28％,残油量5.18％,吐温20含量11.11％,蛋白质回收率84.68％.采用5 kDa超滤膜处理水提液制得花生蛋白粉纯度77.35％,残油量6.14％,吐温20含量6.36％,蛋白回收率97.45％.采用碱盐皂化结合酸沉法制得花生蛋白粉纯度较高,残油量较低,而超滤膜法制得蛋白粉吐温含量较低,蛋白质回收率高,但纯度较低.
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