Baking – Why did the green tea muffins turn black

bakingchemistrycolormuffins

I made green tea muffins following the recipe here. I like my muffins moist and fluffy, so I added banana as suggested by the recipe and replaced half of the baking powder with baking soda. I also added a teaspoon of rice vinegar to activate the baking soda.

Right before baking the mix was vibrantly green, but after 13 minutes in the oven the muffins had turned very dark — and this morning they were even darker.

What happened, and how can I prevent it?

muffins

Best Answer

Your first step would be to stick to the recipe. pH changes are well known to interfere with plant pigments. Adding baking soda and vinegar can very well have interfered with something in the muffins, be it the tea or something else. I am not 100% sure this must have been it, but it is the likeliest reason.

Also, I would recommend against making changes to a recipe before you have tried it as-written. You cannot know how changes affect it, and what unintended consequences they have, until you have established a reference. For example, you cannot know if your addition of baking soda made the muffins both fluffier and darker, or if it only made them dark without any change in fluffiness.