I usually buy Restore, but accidentally ordered George's, and my first experience of trying to mix it didn't really work very well. Can anyone help?

My usual shake is 2 scoops Restore, 2/3c oats, handful blueberries, 1c milk. Yum.

So I mixed 1/3c George's, handful blueberries, 2c milk. Yuk. It was greenish in colour and tasted bad. I was surprised.

Am I mixing it wrongly?

One other possibility is that it was outside in my mailbox all day in the heat here - could that have affected it?

Grateful for any thoughts.

Jill