The molecules of sugar

Glucose, also known as dextrose, is the simplest sugar molecule. Starch is formed from chains of glucose molecules. It is most often encountered in the form of corn syrup, which is made by breaking starch down. Two glucose molecules form maltose. In comparison to sucrose, glucose is less sweet, less water-soluble, and thinner in solution. It caramelizes around 300 degrees F.

Fructose, also known as levulose, is an isomer of glucose. They have the same chemical formula but vary in their structure. Fructose is the sweetest of the common sugars and the most water-soluble. The human body metabolizes fructose more slowly than glucose and sucrose, making it a preferable sugar for diabetics. It caramelizes at 220 degrees F. Fructose molecules exist in various isomers that have different effects on our sweet receptors. The six-corner ring shape is the sweetest. It predominates in cold, acid solutions. This means that manufacturers can use half of the sugar content (and thus half of calories) by using fructose versus sucrose to reach the same sweetness in a cold drink. In warm conditions, the structure changes to a five-corner ring, which drops its sweetness to that of sucrose.

Sucrose, also known as table sugar. It is a compound made from one molecule of glucose and one molecule of fructose. Plants produce sucrose during photosynthesis. It is the form extracted from sugar cane and beets. It benefits from properties of glucose and fructose. It is the second sweetest, second most water-soluble, and most pleasant tasting even at high concentrations. It caramelizes at 340 degrees F. When heated in the presence of acid, sucrose breaks into its single molecules at a ratio of 75% glucose and fructose, and 25% sucrose. This process is referred to as inversion. Invert sugar exists only as a syrup since fructose cannot fully crystalize in the presence of glucose and sucrose. Invert sugars are useful in candy making.

Lactose is a composite of glucose and galactose. It is the sugar found in milk. It is much less sweet than sucrose. It is mostly used to add bulk than sweetness.