What can cause yeast doughnuts to be greasy?

The correct answer relates to the fermentation process of the dough. When yeast doughnuts are allowed to ferment too much, the dough can become overly aerated and weak. This excessive fermentation leads to a compromised structure that fails to retain the proper amounts of gas during frying. As a result, when the doughnuts are fried, they may absorb too much oil, resulting in a greasy texture.

Understanding the fermentation process is crucial for yeast doughnuts. Proper fermentation helps develop flavor and texture, allowing the dough to rise adequately without losing structural integrity. If the dough rises beyond the optimal point, it can collapse when introduced to hot oil, leading to greasy products rather than doughnuts that are light and fluffy.

Other options present different scenarios that do not directly lead to greasiness. Frying at a high temperature, for example, would typically cause doughnuts to cook quickly, reducing absorption of oil. Under-fermented dough may not rise properly, resulting in a denser product that might not be greasy either. Using too little flour could affect the structure but not necessarily lead to greasiness as it would largely depend on the oil absorption dictated by the overall dough condition. Thus, proper fermentation balance is key to achieving desirable results in doughnut texture and flavor.