Self-rising flour is a type of flour that already contains a leavening agent, typically baking powder, along with salt. The inclusion of baking powder in self-rising flour allows it to rise without the need for additional yeast. If you add yeast to self-rising flour, the following outcomes can occur:
Excessive rising: Adding yeast to self-rising flour can result in an excessive rise in the dough. Yeast produces carbon dioxide gas during fermentation, and when combined with the leavening agent already present in self-rising flour, the dough may rise too much and become overly puffy or unstable.
Altered flavor and texture: The addition of yeast to self-rising flour can affect the flavor and texture of the final product. The yeast fermentation process produces different flavors compared to the chemical leavening agents in self-rising flour. Additionally, the texture may become denser or heavier due to the combined action of both leavening agents.
Unpredictable results: Mixing yeast with self-rising flour can lead to unpredictable outcomes. The interaction between the yeast and the chemical leavening agents may not work harmoniously, potentially resulting in an uneven rise or an undesirable texture.
If you want to make a bread or dough that requires yeast, it is generally best to use all-purpose flour or bread flour, which do not contain leavening agents. These flours provide a neutral base that allows the yeast to properly ferment and provide the desired rise and texture.