Final answer:
Sucrose, a non-reducing sugar, does not directly participate in the Maillard reaction because it lacks a free aldehydic or ketonic group necessary for the reaction.
Step-by-step explanation:
The Maillard reaction involves a chemical reaction between amino acids and reducing sugars that gives browned food its desirable flavor. Sucrose does not directly participate in the Maillard reaction because it is a non-reducing sugar, which means it does not have a free aldehydic or ketonic group to react with the amino acids. Therefore, the correct answer to the question of which sugar does not directly participate in the Maillard reaction is D) Sucrose.