Fix my matcha pudding?

In the winter my matcha puddings come out the wrong color.

Every few months I make a batch of matcha puddings for my family get togethers.

In the warm months it comes out perfectly. The matcha settles to the bottom of each cup and the surface is a nice creamy tan color. In the colder months though it seems the matcha never settles, the pudding surface becomes an ugly earthy swirl color.

I believe I've tried to tweak all the obvious problems. A short list includes: warming the baking cups, letting the mixes sit longer, mixing longer/harder, making the oven hotter, heating the mixes at higher temperatures, making the kitchen itself warmer. The ingredients are typical (sugar/half+half/milk/yolk).

One thing i haven't tried is storing the sugar and matcha at a warmer temperature prior to use. I'm not sure if this would really make a difference.