Will boiling sugar turn it from mainly sucrose to dextrose?

Answer 1

Effect of acid and heat on sugar

Sucrose (table sugar) is a disaccharide, meaning it is two simple sugars, glucose and fructose, that have reacted in such a way that they join together, losing a molecule of water in the process. A reaction that produces water is called a condensation reaction. The fructose acts like an acid, and donates a proton. The glucose acts like a base, and donates a hydroxide ion. The proton and the hydroxide ion combine to form water, and the two simple sugars combine to form sucrose.

The reverse reaction, called hydrolysis, is where a water molecule is added to a molecule to break it into two parts. Hydrolysis of sucrose in water happens very slowly all by itself. But if an acid is added, it acts like a catalyst, promoting a faster reaction, but not getting used up in the process. Heating up the solution makes the reaction go even faster.

The result of heating sucrose in water with a little lemon juice or vinegar in it is that much of the sucrose is converted into the two simple monosaccharides. Since fructose is a lot sweeter than sucrose, the result is a sweeter solution, even though glucose is not quite as sweet as sucrose. Since the acid is not used up, the solution is also a little tart, but that can be fixed by adding a weak base like egg whites or baking soda. If there are proteins in the solution, they can also react with the acid to neutralize it.