燕麦分离蛋白疏水性及起泡性研究  

Surface Hydrophobicity and Foaming Ability of Oat Protein Isolates

作　　者：田斌强[1,2] 邓乾春[3] 黄娟[2] 谢笔钧[2] 

机构地区：[1]河南农业大学烟草学院,河南郑州450002 [2]华中农业大学食品科技学院,湖北武汉430070 [3]中国农业科学院油料作物研究所,湖北武汉430062

出　　处：《食品研究与开发》2015年第6期1-5,共5页Food Research and Development

基　　金："十一五"国家科技支撑计划项目(2006BAD27B09)

摘　　要：采用碱提酸沉法从脱脂燕麦粉中提取得到了蛋白含量为93.01%的分离蛋白(OPI),分析其氨基酸组成,并用ANS荧光探针法研究p H、Na Cl、蔗糖、Ca Cl2、Al Cl3和尿素对燕麦分离蛋白疏水性和起泡性的影响。结果表明,OPI氨基酸组成接近FAO/WHO理想模式,p H对燕麦分离蛋白疏水性的影响最大,p H 2时疏水性最强,且酸性环境下的疏水性远远超过碱性环境。不同盐离子对蛋白疏水性的影响程度和趋势不一样,随Al Cl3和尿素浓度增加,OPI疏水性减弱;而Ca Cl2和蔗糖浓度升高时蛋白疏水性增强。Na Cl在低浓度(<0.6 mol/L)时蛋白疏水性减弱,高浓度时蛋白疏水性增强。不同因素对OPI起泡性也具有较大的影响,其变化趋势与疏水性较为一致。另外,蔗糖的加入可提高OPI的起泡稳定性,而加入Na Cl对其有所降低。Oat protein isolates （OPI） were prepared by alkali extraction and isoelectric precipitation from defatted oat groats. OPI contains 93.01%protein. The amino acid composition of the isolates was analyzed , and found that OPI has more hydrophobic amino acids than soy protein isolates and the amino acids composition of OPI is close to the ideal model recommended by FAO/WHO. The hydrophobicity and the isolates were measured using ANS fluorescent probe method at various pH and different concentration solution with NaCl, sucrose, CaCl2, AlCl3 and urea. The foaming ability of OPI was investigated at the same condition. The results showed that pH had the highest influence on the surface hydrophobicity of OPI and the hydrophobicity reaches its peak at pH2;the hydrophobicity of OPI at acid pH was much stronger than that at alkali pH. The trend of effect of different salts on protein hydrophobicity was not same. With AlCl3 and urea concentration increased, the OPI hydrophobicity decreased, but CaCl2 and sucrose was on the contrary. The hydrophobicity decreased in NaCl solution with low concentrations （〈 0.6 mol/L） while hydrophobicity enhanced with concentration rising. Different factors had great influence on OPI foaming , the trend was consistent with the hydrophobic. In addition, the addition of sucrose can improve foaming stability of OPI, and the accession to the NaCl reduced it.

关 键 词：燕麦 分离蛋白 疏水性 ANS 起泡性 

分 类 号：TS210.1[轻工技术与工程—粮食、油脂及植物蛋白工程]