Food Allergy Research and Resource Program, Department of Food Science and Technology, University of Nebraska-Lincoln., Lincoln, Nebraska 68588-6205, USA.
J Food Prot. 2022 Feb 1;85(2):311-322. doi: 10.4315/JFP-21-260.
The detection and quantification of soy protein is important for food allergen management and identifying the presence of undeclared soy proteins. Heat processing and matrix interactions can affect the accuracy of allergen detection methods. The sensitivity of enzyme-linked immunosorbent assay methods can be compromised if protein epitopes are modified during processing. Therefore, a mass spectrometry (MS)-based method was evaluated for the recovery of total soy protein in incurred matrices. MS-based quantification of total soy protein was assessed by using a combination of external and internal standards. The reproducibility of the standard curves was investigated by comparing within-day and among-day variation. Incurred samples were prepared using bread and frankfurters as model food matrices. Several soy-derived ingredients were used to prepare the matrices with varying levels of soy protein (1, 10, 50, or 100 ppm of total soy protein). A pooled standard curve was used to estimate the total soy protein concentration of the incurred food matrices and the percent total protein recovery. The variation of replicate standard curves between days and among all days was not significant. The differences in slopes obtained from replicate standards run on different days were minimal. The most influential factor on the quantitative protein recovery in incurred samples was the effect of the physical matrix structure on protein extraction. The lowest percent protein recoveries, less than 50%, were calculated for uncooked matrices. The cooked matrices had percentage recoveries between 50 and 150% for all total soy protein levels. Other factors, such as type of ingredient, were determined to be not as impactful on recovery. The MS method described in this study was able to provide sensitive detection and accurate quantification of total soy protein from various soy-derived ingredients present in processed food matrices.
检测和定量大豆蛋白对于食品过敏原管理和识别未申报的大豆蛋白非常重要。热加工和基质相互作用会影响过敏原检测方法的准确性。如果蛋白质表位在加工过程中发生改变，酶联免疫吸附测定方法的灵敏度可能会受到影响。因此，评估了基于质谱（MS）的方法，以用于回收加工过程中受损基质中的总大豆蛋白。通过使用外部和内部标准的组合来评估基于 MS 的总大豆蛋白定量。通过比较日内和日间变化来研究标准曲线的重现性。使用面包和法兰克福香肠作为模型食品基质来制备受损样品。使用几种大豆衍生成分来制备具有不同大豆蛋白水平（总大豆蛋白的 1、10、50 或 100ppm）的基质。使用混合标准曲线来估计受损食品基质的总大豆蛋白浓度和总蛋白回收率。日间和所有日间重复标准曲线之间的变化不显著。不同天运行的重复标准曲线的斜率差异最小。对受损样品中定量蛋白质回收影响最大的因素是物理基质结构对蛋白质提取的影响。未煮制的基质的蛋白回收率最低，低于 50%。所有总大豆蛋白水平的煮制基质的蛋白回收率在 50%至 150%之间。其他因素，如成分类型，被确定对回收的影响不大。本研究中描述的 MS 方法能够从加工食品基质中存在的各种大豆衍生成分中提供对总大豆蛋白的敏感检测和准确定量。
