How does yeast react with cornstarch?

Yeast does not have any significant reaction with cornstarch. Cornstarch is a complex carbohydrate composed primarily of glucose units. Yeast, which is a type of fungus, typically reacts with simple sugars like glucose, fructose, or sucrose to produce alcohol and carbon dioxide through the process of fermentation. However, cornstarch, being a complex polysaccharide, is not easily broken down by yeast into simple sugars. Therefore, yeast does not ferment cornstarch effectively and does not produce any noticeable reactions or byproducts.