Food Science & Technology Research Program, School of Public Health, Curtin Health Innovation Research Institute, Curtin University, Bentley, Western Australia, 6102, Australia.
J Sci Food Agric. 2013 Dec;93(15):3755-62. doi: 10.1002/jsfa.6249. Epub 2013 Jul 12.
Australian sweet lupin (ASL) protein is conventionally isolated by alkaline extraction/acid precipitation, leaving a waste stream containing acid-soluble proteins (ASPs) and contaminating raffinose family oligosaccharides (RFOs). The foaming functionality of ASP isolated from ASL is not known, but ASP from another lupin species has demonstrated high foaming functionality.
Pre-soaking ASL kernels increased their protein/RFO ratio; however, some protein was lost by soaking. The foaming capacity of ASL protein isolated by different methods was ranked in the following order: alkaline extraction/isoelectric precipitation < direct acid extraction (novel ASP) < supernatant from isoelectric precipitation (conventional ASP) < ultrafiltered novel ASP = fresh egg white. Electrophoresis indicated enrichment of γ-conglutin and albumin peptides in ASPs and of a single peptide in the fibre residue from alkaline extraction.
The high foaming capacity of ultrafiltered novel ASP, similar to that of fresh egg white, indicates the potential of this lupin protein as a food ingredient for foaming applications.
澳大利亚甜羽扇豆（ASL）蛋白通常通过碱提取/酸沉淀来分离，留下含有酸溶性蛋白（ASP）和污染的棉子糖家族低聚糖（RFO）的废水流。从 ASL 中分离出的 ASP 的泡沫功能尚不清楚，但来自另一种羽扇豆的 ASP 表现出了很高的泡沫功能。
ASL 豆仁的预浸泡增加了其蛋白质/RFO 比例；然而，浸泡会导致部分蛋白质损失。不同方法分离的 ASL 蛋白的起泡能力排序如下：碱提取/等电沉淀 < 直接酸提取（新型 ASP）< 等电沉淀上清液（传统 ASP）< 超滤新型 ASP = 新鲜蛋清。电泳表明，ASP 中富含 γ-伴球蛋白和白蛋白肽，而碱性提取的纤维残渣中则含有单一肽。
超滤新型 ASP 的高起泡能力与新鲜蛋清相似，表明这种羽扇豆蛋白具有作为泡沫应用的食品成分的潜力。
