Question

The absence of _____ and _____ is not an accident, because they would catalyze oxidation, their producing metallic or oxidized flavors.

(a) Lead-casein

(b) Boron-tin

(c) Iron-copper

(d) Zinc-brass

I have been asked this question in unit test.

My doubt is from Milk Quality Farm in portion Quality parameters of Dairy Engineering

Answer 1

Right answer is (c) Iron-copper

For explanation I would say: Iron and copper leads to the formation of metallic and oxidized flavor in milk. They are removed from milk.