There are many possible methods that a cook uses to thicken a sauce. Most of the time the method depends on their intended consistency and flavor. Some popular options include:
Roux (pronounced ‘roo’) is basically a flour and fat mixture that creates a smooth paste, or liquid, that can be used to thicken a sauce. To make a roux, you can use any fat as long as it’s liquid. Add to that some basic, all-purpose flour. Popular fat choices include duck, smoked pork, olive oil, butter, and bacon.
In order to create the mixture, heat approximately ½ to 1 cup of liquid fat, then add to that one tablespoon of flour at a time. Mix well after each addition of flour so that there are no lumps. The total amount of flour added determines how thick your roux will be. If you need a sauce which is very thick, you need to use a drier roux than if you want your sauce to be thin.
The flavor of the roux is affected by the time taken to cook it. The longer it is cooked, the more flavorful it will be. Roux evolves through three stages while cooking, Blond Roux which is met after five minutes of cooking will result in a nutty aroma. Brown Roux is the second stage which is achieved after five minutes of cooking and leads to a roux of greater flavor and darker color. Black Roux is the third stage and is mostly used for Creole or Cajun dishes as its flavor is quite intense.
Making use of cornstarch for thickening a sauce is sometimes referred to as “slurry making.” Add cornstarch to water then mix them together to form a consistent liquid. Add this slurry to some hot water then leave it to boil. Cook for about five minutes in order to get rid of the starchy flavor. The slurry’s consistency directly affects the sauce’s thickness such that the thicker the slurry, the thicker the sauce.
3. Butter and Beurre Manie
Butter, unlike the previous mixtures, has less thickening power and is generally added for finishing up a sauce. Once you add butter, get the sauce off the heat so that it doesn’t scald. After melting the butter, stir up the sauce and let it settle. This helps to cool the butter which will tighten and solidify the sauce.
Beurre Manie, on the other hand, is a French name for butter which is kneaded together with flour. The mixture is kneaded into a smooth dough or until a thick paste is formed. If you are kneading large quantities, you can use a food processor to save your hands! Beurre Manie is mostly used for thickening sauces, gravies, and savory soups.
When the mixture is ready, roll it into small balls then add them to the sauce for thickening. The balls are added individually and the second ball should not be added until the first ball is dissolved. The process continues until you have reached the intended consistency.
4. Potatoes or Potato Flakes
For each cup of sauce, add one tablespoon of mashed potatoes or potato flakes. Potato flakes can be found in any grocery store and are essentially dried and packaged mashed potatoes. However, do not use these flakes in sauces that are clear or have delicate flavors.
Add the flakes slowly into the sauce as it simmers to allow thickening. Add until your required consistency is met.
5. Food Gum
Some of the commonly-used food gums that are used to thicken sauces are guar, pectin, agar and xanthan gum. You only need very small quantities of these gums to thicken the sauce in order not to have any changes to its taste or color.
First, mix the gum with another liquid such as liquid fats. Heat the mixture up then leave it to boil for roughly five to ten minutes. Lastly, pour this mixture into the sauce and stir. However, take note that gums such as xanthan and pectin, are added directly to the sauce without needing to be mixed with fats.
6. Egg Yolks
Using egg yolks to thicken best fits rich cream, pudding, and custard sauces. Crack the egg then separate the white from the yolk. Break the yolk then add small portions of the sauce (while it’s warm) to the yolk. Doing this will help to incorporate the egg into the sauce gradually.
Lastly, add in this thinned egg mixture to the full sauce then boil and simmer until the intended thickness is obtained.
Arrowroot flour is best used when thickening a clear sauce because it adds no scent or flavor to the sauce. It is also highly recommended for vegetarians. Arrowroot is also great to use when thickening substances that are acidic. Make a slurry using arrowroot powder/flour then add it to the liquid you want to thicken. Cook slow and low until you reach your desired consistency.