Clarification of Adhesion Mechanisms of Soils onto the Equipment Wall Surfaces and Its Desorption in Food Manufacturing Process

在这项研究中，我们重点关注以下三个主题，即，1)澄清蛋白质、肽和氨基酸的吸附特性，2）鉴定与固体表面相互作用的蛋白质分子中的肽区域，和3）使用蛋白水解酶和由组合的过氧化氢和紫外线产生的羟基自由基清洁被蛋白质污染的表面的行为。研究了不同条件下β-乳球蛋白、牛血清白蛋白和明胶在不锈钢表面的吸附行为。随着温度的升高，β-乳球蛋白和牛血清白蛋白形成二硫键的吸附量增加，而明胶的吸附量减少。此外，对氨基酸和多肽的吸附行为进行了详细的研究，表明酸性氨基酸在吸附行为中的重要性。研究了胰蛋白酶酶解β-乳球蛋白所得肽段的吸附行为。结果表明，该肽段（^<125>Thr-Pro-Glu-Val-Asp-Asp-Glu-Ala-Leu-Glu-Lys^<136>）具有不可逆吸附行为，该区域可能是蛋白质中的相互作用位点之一。FT-IR分析表明，酸性氨基酸被解离吸附到不锈钢表面上。研究了不同条件下蛋白酶清洗和羟基自由基清洗对不锈钢颗粒的清洗效果，并与碱清洗进行了比较，探讨了其清洗机理。

In this study, we focussed to the following three subjects, i.e., 1) clarification of adsorption characteristics of proteins, peptides, and amino acids, 2) identification of peptide regions in protein molecules that interact with solid surfaces, and 3) cleaning behaviors of the surfaces fouled with proteins using proteolytic enzymes and hydroxyl radicals generated by combined hydrogen peroxide and ultraviolet rays. Adsorption behaviors of β-lactoglobulin, bovine serum albumin, and gelatin onto the stainless steel surface were investigated under different conditions. With increasing the temperature, the adsorbed amount of β-lactoglobulin and bovine serum albumin were increased to form disulfide linkages, whereas that of gelatin decreased. Furthermore, adsorption behaviors of amino acids and peptides were examined in detail, which showed the importance of acidic amino acids in the adsorption behaviors. The adsorption behaviors of peptides obtained by digestion of β-lactoglobulin with trypsin were investigated. It was found that a peptide fragment (^<125>Thr-Pro-Glu-Val-Asp-Asp-Glu-Ala-Leu-Glu-Lys^<136>) showed an irreversible adsorption behavior and this region was thought to be one of the interaction sites in the protein. FT-IR analyses revealed that the acidic amino acids were dissociated on adsorption onto the stainless steel surface. Cleaning behaviors of the stainless steel particles fouled with proteins by enzyme cleaning (proteases) and hydroxyl radical cleaning were carried out under various conditions to compare their performances with caustic cleaning and their cleaning mechanisms were studied.