Caramel is a form of cooked sugar that is used in candies, baked goods, desserts, dips, sauces and other prepared food products.
The Science of CaramelEdit
Caramel is essentially cooked sugar. As sugar increases in temperature, it loses water molecules from its structure and reacts in a process similar to browning that results in the creation of many complex molecules. These molecules provide the deep, rich flavors and colors that make caramel so special.
The stages of a sugar solution are generally described by the solution's behavior when dropped into cold water:
- Thread Stage (230-234°F): the solution thickens into syrupy threads when you pull a spoon out.
- Soft Ball Stage (234-240°F): the solution can be pressed into a soft gooey ball. Used to make soft chewy candies like taffy.
- Firm Ball Stage (244-250°F): the solution can be pressed into a firm ball. Used to make caramels.
- Hard Ball Stage (260°F): the solution can be pressed into a dense, slightly malleable ball. Used to make harder chewy candies.
- Soft Crack Stage (270°F): the solution solidifies into a glass-like solid that slowly bends under light pressure.
- Hard Crack Stage (300°F): the solution solidifies into a hard glass-like solid that breaks or cracks under pressure. Used to make hard candies and brittles.
- Caramel Stage (310-349°F): An advanced crack stage, defined by the development of an amber color that becomes tan, brown and eventually dark brown as the temperature continues to rise. Also defined by the development of caramel flavors which becomes deeper, less sweet and more bitter as it darkens.
- Burned Stage (350°F): The sugar smokes and eventually turns black. It is completely oxidized (burned) and inedible.
As the water evaporates, the sugar solution becomes super-saturated (contains more dissolved solid than can normally be held by water). As a result, the sugar will want to re-crystallize. Once the sugar is dissolved, do not disturb or contaminate the pot or it may spontaneously crystallize into crunchy "candy" and you will have to stir in water and redo this step. The thermal reaction in "wet" caramel causes some invert sugar to be formed, but at least 10% of sugars by mass should be of invert form to prevent crystallization. Adding a tablespoon of corn syrup per cup of sugar is the easiest way to accomplish this at home, and strongly recommended if you plan to make caramels containing anything solid at room temperature, like chocolate or nuts.
Caramelized sugar by itself solidifies to a glass-like consistency. For a softer consistency liquid and/or fat are added. The ingredients listed in the recipes below result in thick but workable products that soften significantly when warmed. By using less liquid and fat or a higher temperature, you can increase the thickness so that the caramel can be used for dipping apples, making chewy candy, nut brittles, or even art.
There are two basic ways to make caramel: the dry method and the wet method. The dry method, which involves slowly heating sugar alone, is more difficult. The sugar begins browning from the edges in, and must be repeatedly folded into the center until all the sugar changes color and before it begins to smoke excessively. And then the other ingredients are rapidly added.
In the wet method, sugar is dissolved in water, then boiled until the water starts to evaporate. And as the water evaporates, the solution passes through the stages of cooking sugar, which reflect the ratio of water to sugar. This ratio is directly proportionate to the temperature so if you understand the stages, you do not need a candy thermometer. Nevertheless, use of a thermometer minimizes the handling of the (very) hot mixture and allows any mistakes to be easily adjusted. If your caramels are too soft, simply heat the mixture a few degrees higher. If too hard, simply add water, stir, and pour at a few degrees lower.
If you're producing caramelized sugar for later use, e.g. making your own invert sugar with a pinch of citric acid (sour salt), you can safely store the hardened caramelized sugar in a glass jar. Simply put the jar in a cold oven, bring to 300°F, and pour. Follow the same procedure when reheating to liquid form to avoid thermal shock.
To create the texture of caramel sauce, you need a 1:1 ratio of fat and liquid. In this recipe, heavy cream (40% fat) is used along with butter to achieve the 1:1 fat:liquid ratio. If you want to substitute milk you will need to use less milk and more butter to keep the ratio. You can also substitute soy-milk and margarine to make a vegan caramel sauce, but make sure to keep the fat:liquid ratio.
This recipe makes approximately 6 cups of caramel sauce. You can easily halve this recipe if you wish. It takes 30-60 minutes depending how quickly you are evaporating the water. If it is sealed in clean canning jars, the sauce can be stored for 3 months without refrigeration. Or store refrigerated for up to 6 months.
- 2 cups water
- 4 cups sugar
- 2 Tbsp corn syrup (optional)
- Pinch salt
- 2 cups Heavy Whipping Cream
- ½ cup (1 stick) unsalted butter, chopped into 1" cubes
- Adding liquid to sugar that is over 300°F is dangerous! Some of the liquid will immediately flash to super-hot steam. To avoid steam burns, stay back from the pot and pour liquids at arms length. Use an oven mitt for your hand.
- When you add your liquid to the hot sugar it will boil violently. To avoid messy and dangerous boil-overs, a 2.5 quart heavy bottomed sauce pan or pot is the minimum, but 3-4 quarts is recommended
- Use a heat proof spatula or spoon such as wood or silicone.
Dissolve the water, sugar and corn syrup over medium high heat until fully dissolved.
Stop stirring and let the solution boil over medium heat. Check on the solution every 5 minutes. You will see the bubbles slow down and get larger. When the bubbles begin to reach 1/2" to 3/4" start monitoring the solution frequently.
When the solution begins to turn amber, get your cream and butter and watch it constantly.
When the solution has turned a shade of caramel that you like (darker is deeper and will start to take on a little bitterness), step back and add the cream at arms length, stirring constantly and scraping the sides of the pan.
Add the butter and stir until incorporated. Pour the sauce into a serving dish for immediate serving with bread, drizzled on ice cream, as a garnish or for use in other desserts.
If you desire, follow standard canning procedures and distribute into canning jars. Allow to cool until the buttons are depressed. Any jars with buttons that are not depressed should be refrigerated and consumed first. To reheat the caramel sauce, microwave the jars (without covers) for 10-30 seconds depending how soft and hot you want it.
The following are all variations that can be made at different stages of the recipe above.
Simple Syrup: The first step in the recipe was to dissolve two parts sugar in one part water. This creates a simple syrup, perfect for sweetening cold drinks (e.g. Iced Tea) without having to wait for granulated sugar to dissolve.
Caramel Chews: Replace the cream with 3/4 Cup Half & Half. Pour the hot mixture onto a silicone mat or parchment paper to cool. When it is cool enough to handle, fold and knead the caramel a few times, then break into bite size pieces. Allow to cool completely before wrapping individually.
Turtles: Replace the cream with 3/4 Cup Half & Half. Pour the hot mixture over 4 cups of your favorite nut on a silicone mat or parchment paper to cool. When it is cool enough to handle, fold and knead the caramel until the nuts are fully distributed, then break into bite size pieces. Melt chocolate over a double boiler or in the microwave and dip the turtles or simply drizzle chocolate on top.
Toffee: Instead of cream, use 7 sticks of butter (a total of 8 sticks or 4 cups, so you have equal parts butter and sugar). Mix in chopped nuts if desired. Pour onto a silicone mat or parchment paper or molds. After cool drizzle or dip with chocolate and chopped nuts.
Nut Brittle: Do not use any cream or butter. Stir in 1/2 tsp. baking soda (optional), then pour the molten caramel over 4 cups of your favorite nuts on a silicone mat or parchment paper and let it cool. When it has reached room temperature, break it up with a mallet or by dropping the sheet on the counter. Wrap and store in an air-tight container.
Sugar Art: You can do this at any point during the hard crack or caramel stages. Remove the sugar from the heat and allow to cool for one minute. Using a spoon, let the syrup drip off. If it drips in globs, let it cool longer. If it drips in a continuous stream, you can start making art. Drizzle the syrup in patterns over a silicone mat or parchment paper and allow to cool, then carefully peel off. Or, spray bowls and other (clean) objects with cooking spray and drizzle the syrup to create domes and other shapes. Allow to cool to room temperature, then serve soon or store in an air tight container. These will eventually soften and droop from humidity in the air.
Scientific theories and explanations based on information from Good Eats by Alton Brown on the Food Network.