Yes I have been noting the difference in the colour of my whey and the colour that you get, and it is interesting, because the white'ish colour is the colour that both my Maltese friend and I regardless of whether we use junket tablets, or rennent, and we are using both at the recommended rate.
I am going to have a try at adding more rennet than recommended when I next make cheese, and see if I can get the whey that you al get.
Wish me luck.