Yes, you can add whole pieces of fruit to the Jel. If you are adding fruit juice just make sure you keep within the exact measurements and you should be fine. Also, avoid adding high acid fruit/juice such as lemon or pineapple as this will prevent the dessert from setting.
If you are using fruit juice please make sure the 1 1/3 cup is heated to boiling temperature or the Jel will not set.
