Cane sugar, or sucrose, is NOT the same as HFCS, High Fructose Corn Syrup. Cane sugar, or Sucrose, is a disaccharide, a single molecule compose of two monosaccharides, glucose and fructose, with a glycosidic bond (an oxygen atom shares an electron with a hydroxide ion at the reducing end of both monosachharides). While Sucrose is broken down into Glucose and Fructose during digestion in the stomach, it does not break down in the mouth, and has a sweeter taste in the mouth than either glucose or fructose. High Fructose Corn Syrup, on the other hand, is composed of a mixture of glucose and fructose, including both isomers of each (both Glucose and Fructose each have two isomers, or molecular structures, but only one isomer of Glucose and only one isomer of Fructose are capable of bonding to produce Sucrose), with Fructose being the dominant ingredient. While both Glucose and Fructose produce a "sweet" taste on the tongue, neither is as sweet as Sucrose. Also, Sucrose is much more stable and hydroscopic (water attracting) than either Glucose or Fructose.. Carmel is nothing more than the result of breaking down or altering sugars through the application of high heat. If you create a simple syrup with sugar (table sugar, or Sucrose) and water in a sauce pan and continue heating until some of the water has boiled away, when the temperature gets high enough, the bond holding the Glucose and Fructose together as Sucrose will break down; higher still, the Glucose and Fructose will start to break down and reform into other sugar forms. While there are only three dietary sugars - i.e., monosaccharides capable of being directly absorbed into the bloodstream and used for cell function - there are hundreds, even thousands of other sugars, each with its own effect on human taste buds. When the syrup starts turning from clear to amber to (ultimately) a deep mahogany brown, you have the mixture of hundreds of those different sugars that produce the complex flavor experience that is carmel. Trap the sugars in a matrix of butterfat and milk solids with the addition of butter and heavy cream, and some salt (which, through ionic action, intensifies the "sweet" receptors on your tongue) and you have the taste treat which is carmel. Cook the sugars too long or at too high a heat and you'll break it down completely, allowing all the oxygen and hydrogen to escape as water and leaving nothing but carbon - and charcoal doesn't taste good.
BTW, while Cane Sugar and Beet Sugar are both composed of chemically identical Sucrose, Cane Sugar is typically a higher purity than Beet Sugar, and a very sensitive palate can sometimes taste the difference.