Grey zucchini bread

After I slice homemade zucchini and carrot bread, the top half starts to turn grey. This seems to happen when exposed to air. Any ideas what I am doing wrong or what I can change. Here is a link to the recipe I follow:

Thank you!

Tucker Mahoney


boulangere January 2, 2013
You may be experiencing Maillard browning, essentially the browning of a carbohydrate in the presence of a protein. It's happened to me when I've accidentally omitted the baking powder from a recipe for carrot cake which calls for both it and baking soda. It never hurts to double-check one's ingredients, especially when distractions, such as life in general, abound.
Lindsay-Jean H. January 2, 2013
I've had this happen to me before with carrots in cookies before - although more green than grey. A quick internet search led me to believe that I didn't mix in the baking soda well enough. You can read more about it here: Perhaps the same thing happened to you?
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