In skim milk (no fat globules), it is the casein micelles that give milk it's turbidity making the milk completely opaque and white. The concentration of protein in cow's milk on average is 3.3% (w/w) with 2.6% being the casein and about 0.7% the whey proteins (which contribute no turbidity).
The casein micelles are on average 200 nm in diameter. On the other hand if you had kappa carrageenan with a similar length of 200 nm (radius of gyration of approx. 100 nm with MW~1,000,000 g/mol and intrinsic viscosity of 15 dl/g) at that same concentration (2.6%), it would be a firm, solid gel yet would be completely transparent while the skim milk at this concentration is a completely turbid low viscosity liquid.
The difference is due to the shape where casein micelles are large but globular in shape which can scatter light well while kappa casein is large but extended & linear which allows light to pass through easier.
So in my opinion there are more variables that make your question difficult to answer without knowing the molecular dimensions (size and shape), not to mention interaction effects/A2 second virial coefficient (does the system prefer polymer-polymer or polymer-solvent interactions).