The Basics of Caramelization
What is Caramelization?
Caramelization is a non-enzymatic browning reaction that occurs when sugar is heated. As the name suggests, this is the process by which caramel is made from sugar, but it can also happen to other foods that contain sugar (like fruits and vegetables). While both cause food to turn brown, caramelization is different from the Maillard reaction as the reaction does not include amino acids, only sugars. Caramelization is also different than burning which occurs at temperatures so high that sugar breaks down into carbon.
Conditions Needed
Caramelization is still a poorly understood process, but there are necessary conditions that are known. The temperature needed to achieve caramelization is dependent on the type of sugar. Some examples are:
Fructose: 105 °C (221 °F)
Glucose: 150 °C (302 °F)
Galactose: 160 °C (320 °F)
Sucrose: 170 °C (338 °F)
Maltose: 180 °C (360 °F)
Notice that lowest caramelization temperature is still higher than the boiling point of water, so caramelization can only happen in dry-heat environments or while deep frying in an oil that is above the required temperature.
The presence of impurities and/or non-neutral pH (acidic and basic) can speed up the reaction.
Color and Flavor Changes
As mentioned earlier, caramelization changes the color of food. You have probably noticed if you have made homemade caramel that the sugar takes on an amber and then brown color as it heats. The level of browning depends on the types of sugar and the temperature at which the food is cooked. For example, food containing fructose will turn browner faster because it has the lowest caramelization point.
Caramelization also changes the flavor of foods. The exact flavors are dependent on the type of sugar and the byproducts produced in the chemical reactions, but can often be described as nutty, buttery, or toasty. This should not be confused with the bitter flavor caused by burning. Because of the flavors produced, caramelizing ingredients is a great way to add additional layers of flavor to your baked goods.