Caramelization

Caramelization is one of a class of reactions, with many subclasses, in food chemistry, which induces browning and flavor changes in foods, principally sugars. Other classes include the Maillard reaction and enzymatic browning.

At its simplest, caramelization is the process of removal of a water molecule from a sugar molecule, "followed by isomerization and polymerisation steps. In reality the caramelization process is a complex series of chemical reactions, which is still poorly understood."

There are three basic stages:

1. Heating to melting and foaming/boiling. In this stage, disaccharides such as sucrose will decompose into simple sugars, such as glucose and fructose. At lower temperatures, the simple melting will produce changes in the physical form of the sugar, without, at first, color or flavor changes. The resultant forms, however, are vital as the physical base of candies (e.g., marshmallow,fudge)
2. Condensation when the sugars lose H₂O and then interact to produce substances such as difructose anhydride
3. Fragmentation and polymerization, the former tending to be associated with color production and the latter with flavor production.

Heat effects

Temperature	Name	Effect
100°C/212° F	Melting	Evaporation of water; impurities rise to surface, often as foam
102C/216F	Small thread	A spoon dipped into the melt produces a thin thread; used as a base for frostings; no color or flavor change; soft when cooled
104C/220F	Large thread	A spoon dipped into the melt produces a thick thread; used as a base for preserves; no color or flavor change; soft when cooled
110-115C/230-F	Small ball	A spoon dipped into the melt produces small discrete balls; used as cream candy fillings, Italian meringue, fondants, fudge, and marshmallows; no color or flavor change; semi-soft when cooled
110-115C/230-F	Large ball	A spoon dipped into the melt produces large discrete balls; used in soft caramel; no color or flavor change; firm but chewy when cooled
/234-F	Light crack	The syrup dripped into cold water produces light cracked candy; used in semi-hard candy; no color or flavor change; semi-hard when cooled but bends under pressure
165-166/	Hard crack	The syrup produces candy that will crack or shatter; used in hard candy on cooling; no color or flavor change; semi-hard when cooled
	Extra-hard crack	The syrup produces candy that will shatter like glass; used in extra-hard hard candy no color or flavor change; hard when cooled -	310F	Light caramel	Color and flavor change begins
350F	Burned	Color and flavor change begins