What sugars give a positive fermentation test?

A positive fermentation test typically indicates the presence of fermentable sugars such as glucose, sucrose, and lactose. These sugars are metabolized by yeast or bacteria, producing gas and/or acid as byproducts, which can be detected in the test. For example, in a carbohydrate fermentation test using phenol red broth, a color change and gas production indicate successful fermentation of these sugars.