Question

7. When sugar is heated, it melts, then turns brown and finally, turns black. What is this process
called and what kind of change is it?​

Answer 1

Caramelization refers to the browning of sugar. It’s the process that causes sugar to acquire a brownish hue when it’s heated. You could also say that it’s the oxidation of sugar, or the degradation of sugars under heat.

Answer 2

The polymers, divided into three groups – caramelans (C24H36O18), caramelens (C36H50O25), and caramelins (C125H188O80) – are responsible for the browning of sugar. On the other hand, volatile compounds like diacetyl, Hydroxymethylfurfural, diacetyl etc. are responsible for the characteristic ‘caramel smell’.

When granulated sugar is first heated, it begins to melt. As it melts, its color starts to change from white to golden brown, and then to dark brown (if you continue heating it).If you apply heat for even longer, it becomes black and gives off unpleasant fumes. It even tastes different at that point, but do you know what processes are at work here?

In order to understand why sugar turns brown when melted, and ultimately turns black, it’s imperative to first understand what sugar actually is.