I've been using liquid Annatto in any recipe where a yellow color is desirable.
I buy mine from The Dairy Connection and it really is a nice product.
Previously I purchased from leeners and found it to be a really weak product. You are only supposed to add about two to three drops per gallon of milk but I saw absolutely no color change following this procedure.
It may be that I simply got a bad bottle or I might possibly could have been using it wrong. Regardless, I have had great success using the Annatto I bought from the above listed source.
Their double strength Annatto works perfectly. I typically use about 1/16 tsp. per two gallon batch and get a really nice orange/yellow color. I also bought a pint of this product for just a little more than a two ounce bottle on the other site.
I have this thing about eating things that don't look as they should.
If I'm eating a cheddar I really need it to be yellow.
I remember a few years ago, there was this green ketchup that became popular in the states. My kids loved it, but I couldn't go near it.
I tasted it once and have to say that it tasted the same as regular red ketchup. My problem was dipping a perfectly good french fry in something that looked so nasty.
Even though it might not be totally natural, the cheese I've always eaten has a yellow color (with some exceptions). Because of that, I want my cheese to be the same.
Oh, one more thing....
From what I've read, certain milk from certain cows at certain times of the year, did produce a nice yellow/orange color. The quality of the milk, used, could be judged from the finished cheese color.
Now it would be really nice to be able to produce a natural yellow color to my cheese from my milk source but since mine comes from the local IGA store, I don't see that as an option. Becasue of that, Annatto is the answer.
Besides, I got really tired of hearing my kids say "Why is your cheese WHITE?!?"