Carotenoids are the compounds responsible for yellow, orange and red colours in many fruit, vegetable and algal sources. Within each source, carotenoids vary in concentration, proportions and chemical structure, all of which influence how it can be used in a food product.
When heat is added to a substance, the molecules and atoms vibrate faster. As atoms vibrate faster, the space between atoms increases. The motion and spacing of the particles determines the state of matter of the substance. The end result of increased molecular motion is that the object expands and takes up more space.
Heat energy, also referred to as thermal energy, is really the effect of moving molecules. Matter is made up of molecules, which are in continual motion and in a solid, vibrate about a mean position. The motion of any molecule increases when the energy of the substance is increased.