Calories in sourdough starter
When I make a recipe for my cooking, I always calculate the nutrition values. I can't seem to calculate the nutrition values and calorie content of a loaf of sourdough bread. I don't have problems with other ingredients except the starter and/or the sponge. I hope some of you will be able to enlighten me in this department.
Say, if I use a starter that is made of equal amount of water and flour, that means only half of the total weight contains caloreis. If I use 10 oz of that starter to mix with 10 oz of water and 10 oz of flour, out of the total 30 oz only 15 oz contain calories, so I should only add calories for 15 oz flour (or half of the total weight) into my recipe, am I correct? Is there anything else I should take into consideration?