Erica asks: I would like to make blueberry muffin batter ahead and then just pour into muffin tins & bake Christmas morning. I was thinking I could make the batter then add fresh blueberries right before I bake. Will this work if I make the batter the night before?
Baking S.O.S. says: Baking powder, which makes the muffins rise, will start to react as soon as you mix the wet ingredients with the dry. You will get the most leavening (rising) from your batter if you bake it right away. Over time, the baking powder will lose its effectiveness if you allow the batter to sit too long before you bake it.
But having said that, I used to work at a bakery where we would mix up the muffin batter the night before, store it in the refrigerator, then bake it off the next morning so the muffins would be hot and fresh. Storing the batter in the refrigerator will help slow down the baking powder reaction so that it does not lose as much leavening power. It should be just fine if you only store it in the frige for one night. (don’t hold it any longer than that, though)
Also, using fresh blueberries with this method is a good idea. Frozen blueberries would thaw in the batter and release their juices, turning the entire batter purple. I hope you have a very enjoyable Christmas morning!