Abstract Fat-replacers can be applied to enhance creaminess as they often possess a high ability to bind water. Especially for mixed biopolymer complexes, such as whey protein–pectin complexes (WPPC), the viscosity measurement can show non-linear behaviour, impairing exact calculations of bound water or elucidating the structure from the intrinsic viscosity. By means of mass balance based on ultra-centrifugation and capillary viscosimetry, an alteration in biopolymer ratio during thermal stabilisation was determined. The initial ratio of 5:1 (w/w) shifted in favour of the protein component in the complex. 98% of the pectin were not incorporated in the complex but remained in the outer phase increasing its viscosity. By considering this alteration, the voluminosity of WPPC was calculated to be 18.3 ±0.5 mL g−1. Supplementary scanning electron micrographs showed a porous complex structure dominated by denatured whey proteins, which were linked by few pectin molecules. A model of the thermally induced complex formation from whey protein isolate and low-methoxyl pectin was postulated in which the unbound pectin plays a catalyst-like role.

中文翻译：

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确定热稳定前后乳清蛋白-果胶复合物的生物聚合物比例

摘要 脂肪代用品通常具有很强的结合水的能力，因此可用于增强乳脂状。特别是对于混合生物聚合物复合物，如乳清蛋白 - 果胶复合物 (WPPC)，粘度测量会显示非线性行为，影响结合水的精确计算或从特性粘度阐明结构。通过基于超离心和毛细管粘度测定的质量平衡，确定了热稳定过程中生物聚合物比率的变化。5:1 (w/w) 的初始比例有利于复合物中的蛋白质组分。98% 的果胶没有掺入复合物中，而是留在外相中，增加了其粘度。通过考虑这种改变，计算出 WPPC 的体积为 18.3 ±0.5 mL g-1。补充扫描电子显微照片显示了由变性乳清蛋白主导的多孔复杂结构，其由少数果胶分子连接。假设了一种由乳清蛋白分离物和低甲氧基果胶形成的热诱导复合物模型，其中未结合的果胶起到类似催化剂的作用。