What is the result of caramelisation of sugar when it is heated?

Caramelisation of sugar is a process that occurs when sugar is heated to a certain temperature, prompting a series of complex chemical reactions. During this process, the sugar molecules break down and react with each other, leading to the formation of new compounds. One of the most notable results of caramelisation is the browning of the sugar, which not only influences its color but also transforms its flavor profile. The resultant caramel is characterized by a rich, deep brown hue and a complex, sweet flavor with nutty and slightly bitter notes, distinguishing it from raw or granulated sugar.

This transformation is crucial in cooking and baking, as it adds depth and richness to a variety of dishes and desserts. It's important to note that the other options do not accurately represent the process: sugar does not become less soluble or turn white during caramelisation, nor does it crystallize; rather, it transforms into a liquid state that is typically syrupy and thick as the caramel forms.