Abstract Non-fat acidified milk model systems were constructed from frozen casein and whey protein concentrates produced from skim milk using membrane filtration, and combined with commercial whey protein ingredients, i.e. nano-particulated whey protein (NWP), micro-particulated whey protein (MWP), and whey protein concentrate (WPC). Model systems were characterised in terms of particle size distribution and fractionation, surface hydrophobicity and accessible thiol groups, rheological behaviour, water holding capacity and graininess. Samples containing NWP exhibited higher surface hydrophobicity and increase in accessible thiol groups, shorter gelation time, higher gelation pH and G’, but increasing particle size and number of grains, when compared with addition of MWP and WPC. Addition of MWP resulted in weak gels with a less connected protein network and decreased number of grains. Mixtures of NWP and MWP (1:1) had rheological properties closer to those seen for MWP. Systems with WPC differentiated themselves with a large quantity of small aggregates.

中文翻译：

---

在非脂肪酸化模型系统中添加的乳清蛋白成分与天然牛奶成分之间的相互作用

摘要 脱脂酸化牛奶模型系统由脱脂牛奶生产的冷冻酪蛋白和乳清蛋白浓缩物通过膜过滤，并结合商业乳清蛋白成分，即纳米颗粒乳清蛋白（NWP）、微颗粒乳清蛋白（MWP）构建而成。 ) 和乳清蛋白浓缩物 (WPC)。模型系统的特征在于粒度分布和分级、表面疏水性和可接近的硫醇基团、流变行为、持水能力和颗粒度。与添加 MWP 和 WPC 相比，含有 NWP 的样品表现出更高的表面疏水性和增加的可及硫醇基团、更短的胶凝时间、更高的胶凝 pH 和 G'，但增加了颗粒大小和颗粒数量。添加 MWP 导致凝胶较弱，连接的蛋白质网络较少，颗粒数量减少。NWP 和 MWP 的混合物 (1:1) 具有更接近 MWP 所见的流变特性。具有 WPC 的系统通过大量的小聚集体来区分自己。