I was supposed to use all purpose flour in my yeast roll recipe, but used self-rising. What will happen now?--Sarah
As described in the earlier post on Self-rising Flour, it is regular flour that has baking powder and and salt added. The exact formulas, including the type of baking powder used, vary by manufacturer.
There are two problems you are likely to encounter. The first is fairly easy to predict and likely the biggest factor. Your bread will likely be a lot saltier than usual, due to the extra salt in the self-rising flour.
The second is a bit more difficult. Because you were making yeast rolls, you now will have two leaveners in the same batch -- the yeast called for in the recipe, and the baking powder from the self-rising flour -- so your rolls will likely over-inflate. How much, and what happens because of it depends on the recipe and method, as well as the flour. According to the USDA, self-rising flour has about 0.5% less protein than all-purpose. The two proteins glutenin and gliadin in flour bond with the water and with each other to form gluten. Gluten is the magic ingredient in making bread and rolls, since it is what allows bread to hold in the expanding gases produced by yeast and heat to make it rise and give it texture. By comparison, cake flour has around 1.7% less protein than all-purpose. When making cakes and biscuits, you don't want gluten to form, which is why you start with a flour that has less protein.
So, the self-rising flour has less protein, which means it will form less gluten and therefore be less able to hold in the gases. Because the difference in percentages is small, the effect may be small, but the double leavening will take its toll. What is quite likely to happen is either rolls that rise way too much in the oven, or rolls that rise well and then collapse in the center leaving a cratered crust.
You may also see a slight difference in the color of the crust or the amount of time that it takes the rolls to bake due to the presence of the baking powder.