But glucose is easier to break down than sucrose and starch. Glucose is monosaccharide. They are the simplest carbohydrates. Through glycolysis and later in the reactions of the Citric acid cycle (TCAC), glucose is oxidized to eventually form CO2 and water, yielding energy, mostly in the form of ATP.Sucrose is a disaccharide, consists of 2 monosaccharides. While starch is a polysaccharide, a complex carbohydrate.ot all yeast produce and secrete amylase, and it would take time to do this. Hence why little to no CO2 Sucrose (a glucose-fructose di-sacharide) is fairly small, but it too needs to be broken down into individual glucose and fructose molecules.