When the mixture of a food substance and Benedict's solution was warmed, the solution changed from blue to black-red. This indicates the presence of

Answer Details

The presence of reducing sugar is indicated by a change in color from blue to black-red when a food substance is mixed with Benedict's solution and heated. Benedict's solution is a chemical reagent used to detect the presence of reducing sugars, such as glucose, fructose, and maltose. When Benedict's solution is mixed with a food substance containing reducing sugar and heated, a chemical reaction takes place, causing the solution to change color from blue to green, yellow, orange, or red, depending on the amount of reducing sugar present. If the amount of reducing sugar is high, the solution may turn brick-red or even black-red in color. This color change is due to the reduction of copper ions in the Benedict's solution to copper oxide, which is a black or reddish-brown solid. In contrast, fatty acids, sucrose, and amino acids do not react with Benedict's solution, and therefore, do not cause a color change from blue to black-red when mixed with the solution and heated.