等离子体对花生蛋白功能特性和结构的影响

Effects of Plasma Treatment on Functional Properties and Structure of Peanut Protein

采用常压等离子体射流对花生蛋白进行改性,并对其功能特性、结构和热特性进行表征。结果表明:花生蛋白经等离子体处理150 s,其溶解性、持水性和吸油性分别提高了278%、25.9%、73.7%。花生蛋白分子粒径变小,大分子蛋白聚合物解聚为小分子物质。随着处理时间的延长,二级结构中β-折叠含量逐渐降低,β-转角含量不断提高,蛋白结构由紧密变松散。等离子体处理30~60 s时,紫外最大吸收波长(λmax)蓝移,吸收峰升高,三级结构改变,蛋白分子展开。处理90~150 s时,λmax红移,吸收峰下降,大分子蛋白解聚。差示扫描量热法结果表明,花生蛋白在等离子体处理后,花生伴球蛋白具有更多有序的空间构象,其变性协同性降低,而花生球蛋白空间构象有序度降低。等离子体处理通过大幅改变花生蛋白的分子结构和粒径分布,显著改善其功能特性。

Plasma jet under normal pressure was used to modify peanut protein,and thefunction,structure and thermodynamic properties were studied.The results indicated that the peanut protein was treated with plasma for 150 s,and its solubility,water holding capacity and oil absorption increased by 278%,25.9%and 73.7%,respectively.The particle size of peanut protein became smaller,and the macromolecular protein polymer was depolymerized into small molecular substances.With the increase of treatment time,β-sheet content of the secondary structure gradually decreased,β-turn content continuously increased,and the protein structure changedfrom compact to loose.When plasma treatment lasted for 30~60 s,the ultraviolet maximum absorption wavelength(λmax)was blue-shifted,the absorption peak increased,the tertiary structure of the protein changed,and the protein molecules expanded.When plasma treatment lasted for 90~150 s,theλmax was red-shifted,the absorption peak decreased,and the macromolecular protein depolymerized.Differential scanning calorimetry indicatedthat,after the plasma treatment,the arachinhad more order spatial conformation,and the denaturationcooperativity decreased.While the degree of order of arachin was lowered.Plasma treatment significantly improved the functional characteristics of peanut protein by significantly changing the molecular structure and particle size distribution.