Question

A cow eat grass but it's milk does not turn green? why?​

Answer 1

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Milk is neither green like grass nor red like blood because the amino acids, sugars, minerals and fats from the grass are completely repurposed as milk which is typically white, though yellowish (or golden) from Guernsey and some other cows, and I understand yaks have pinkish milk.

Answer 2

Answer:

We, human beings eat food and excrete out the harmful substances.

Cows eat grass and give out milk as the grass inside their body is digested and we can also treat it as natural!

In human beings, the food gets digested and the whole process occurs and hormones and many enzymes are released inside our body which we study about.

I am not very particular about this but may be if we study about animals more, we will get to know!

In a nutshell, we can say that it's natural as they eat grass it gets digested and we are able to get milk from her body!