Cutzal 50-50 (if I remember correctly) is a typical mineral oil based coolant. We used to have that in some old multi-spindle bar machines at work. It was milky looking, I never did care for the stuff. It used to breed bacteria, unless we aerated the coolant tanks. I wouldn't put that in any of my engines. We eventually switched most of our machines to a full synthetic product.
For my trucks, I'll stick with a good antifreeze.
John
