When you burn toast what is the burnt stuff made of?

When you burn toast, the burnt parts primarily consist of carbon, along with various compounds formed from the breakdown of sugars, proteins, and fats present in the bread. The heat causes these organic materials to undergo pyrolysis, resulting in the formation of char and smoke, which contain a mixture of carbonaceous residues and volatile compounds. Additionally, harmful substances like acrylamide can form during the high-temperature cooking process.