When you add flour to cookie dough, it can become sticky due to the nature of the flour and its interaction with the other ingredients. The stickiness is primarily a result of the gluten-forming proteins present in the flour and the absorption of moisture.
Gluten formation: Flour contains two main proteins, glutenin and gliadin, which combine to form gluten when mixed with water. When you add liquid ingredients (such as eggs or milk) to the cookie dough, the flour proteins absorb the moisture and begin to form gluten. Gluten provides the dough with its elastic and cohesive properties, which are essential for giving structure and texture to the cookies.
Hydration of flour: As the flour absorbs liquid from the other ingredients in the dough, it becomes hydrated. The hydration process causes the starch molecules in the flour to swell and absorb water, contributing to the sticky texture.
To manage the stickiness of cookie dough, here are some tips:
Add flour gradually: When mixing the ingredients, add the flour in small increments, allowing the dough to absorb the moisture slowly. This can help prevent the dough from becoming excessively sticky.
Chill the dough: After mixing the dough, you can refrigerate it for some time. Chilling the dough can firm it up and make it easier to handle.
Use floured hands or surfaces: When shaping the dough into cookies, lightly flour your hands and the work surface to reduce sticking.
Adjust the recipe: If the dough is still too sticky, you can add a little more flour (in small amounts) until you reach the desired consistency. However, be careful not to add too much flour, as it can negatively affect the texture and taste of the cookies.
Consider the humidity: High humidity in your kitchen or environment can affect the dough's stickiness. In such cases, you may need to adjust the amount of flour or chilling time accordingly.
Remember that the exact stickiness of cookie dough can vary based on the specific recipe, the type of flour used, and other factors. By understanding the role of flour and gluten in the dough-making process, you can better control and adjust the stickiness to achieve delicious, well-textured cookies.