There are a few things that you can do to prevent your food from turning black. One thing you can do is soak your wood chips in water for about an hour before putting them on the smoker. It will help create a barrier between the heat and the wood, preventing the carbon from being deposited on your food. Another thing that you can do is to use a different type of wood, such as hickory or oak. These types of wood will not deposit as much carbon on your food.