If I could know the viscosity measuring it by myself I would have done it, so that means, that I cannot measure it by myself, therefore I'm asking for it. Anyway thank you very much for giving an answer.
Milk is not a solution but an emulsion of fat globules and a suspension of casein micelles all suspended in an aqueous serum phase, in which water (cow milk) content is about 82% mass. Therefore, mixing 77% water with 33% powder should still not be a true solution. What do you think ?
Hire a laboratory to do a proper rheological study on the solutions of interest, buy a rheometer and investigate it yourself, or buy a Brookfield viscometer and do the best you can. If you don't know the rheology, you CANNOT design any equipment. Oh, you could guess at it! But that is not science!
If you would like an inexpensive way to measure viscosity try making a small batch of the solution and use a Zahn or Ford cup. They work by draining the fluid out of a certain size hole while you measure the time with a stop watch. The time for that size hole then correlates to cps. I think you can find them at mcmaster.com but you will find them for sale if you google the names.