A reducing sugar is a mono- or oligosaccharide that contains a hemiacetal or a hemiketal group. All monosaccharides above are reducing sugars, and all polysaccharides are non-reducing.

What is the difference between a reducing sugar and polysaccharides?

The main difference between reducing sugar and starch is that reducing sugar can be either a mono- or disaccharide, which contains a hemiacetal group with a one OH group and one O-R group attached to the same carbon whereas starch is a polysaccharide, consisting of numerous glucose units joined by glycosidic bonds.

What are reducing and nonreducing sugars?

What is reducing sugar and nonreducing sugar? Any carbohydrate that is capable of causing the reduction of some other substances without being hydrolyzed first is the reducing sugar whereas sugars that do not possess a free ketone or an aldehyde group are called the non-reducing sugar.