Dirty ovens are unhealthy, and the biggest problem of all is the grease! The invisible grease build up that you can’t see, yet you can smell! It is the same dirty oven grease that coats every meal you cook. Grease is a natural by-product of cooking, and we all enjoy cooking. Olive oil, butter and meat fats all naturally contribute to the gradual build up of invisible, smelly and dirty oven grease. So in this context, you should not be embarrassed by any build up of dirty oven