Food Thickening Agents

I've decided to devote a separate page to food thickening agents. Why? Well, as noted elsewhere in my website, attaining a certain expertise with sauce making is a big part of becoming a gourmet cook. And one cannot achieve this without a good understanding of the various food thickening agents used to finish the many varieties of sauces.

One of the most common methods for thickening sauces is through the gelatinization of starches. Gelatinization is the process by which starch granules absorb moisture when placed in a liquid and heated. As the moisture is absorbed, the product thickens. Starches used to thicken sauces are cornstarch, flour, and arrowroot.

Here are the most common food thickening agents:

Roux

Roux is used to thicken sauces. It is a combination of flour and fat, cooked together to form a paste.

The three types of roux are:

1. White roux should be removed from the heat as soon as it develops a frothy, bubbly appearance. It is used in white sauces where little or no color is desired.
2. Blond roux is cooked a little longer than white roux. It should take on a little color. It is used in ivory-colored sauces.
3. Brown roux is cooked until it develops a darker color. Brown roux is used in brown sauces. More brown roux is required to thicken a given quantity of liquid.

Procedure for Preparing Roux

1. Use a heavy saucepan to prevent scorching. Heat the butter or other fat.
2. Add all the flour and stir to form a paste. It is best to use cake or pastry flour because it contains a higher percentage of starch.
3. Cook the paste over medium heat until the desired color is achieved. To avoid burning, stir the roux often. A good roux will be stiff and will not pour well.

Incorporating Roux Into a Liquid

1. Cold stock can be added to the hot roux while stirring with a whisk.
2. Or you can add room-temperature roux to a hot stock while stirring with a whisk.
3. After the roux is incorporated into the liquid, cook the mixture for 20 minutes to remove any flour taste.

Guidelines for Using Roux

1. Do not use aluminum pots so that the sauce doesn't turn gray because of the scraping action.
2. Use heavy pots to prevent sauces from scorching or burning.
3. Avoid extreme temperatures. Roux should not be too hot or too cold.
4. Avoid overthickening.

Cornstarch

Cornstarch, a natural food thickening agent, is a very fine white powder, a pure starch derived from corn. Liquids thickened with cornstarch have a glossy sheen. Products thickened with cornstarch should not be reheated.

Incorporating Cornstarch

Cornstarch must be mixed with a cool liquid before it is introduced into a hot one. A solution of a starch and a cool liquid is called a slurry. It may be added to a hot or cold liquid. It must be stirred continuously if added to a hot liquid.

Arrowroot

Arrowroot is a food thickening agent that is similar to cornstarch because of its appearance and thickening power. It is derived from the roots of several tropical plants. It produces a clearer finished product and it is more expensive than cornstarch.

Buerre Manie

Beurre manie (burr mahn-yay) is a food thickening agent combining flour and soft, whole butter. The flour and butter are kneaded together until smooth. The mixture is then formed into pea-sized balls and whisked into a simmering sauce. It is used for quick thickening at the end of the cooking process.

Liaison

Another food thickening agent known as a liaison is a mixture of egg yolks and heavy cream. It adds smoothness with minimal thickening. The egg yolks could curdle in the sauce so special care should be taken.

Procedure for Using a Liaison

1. Whisk together one part egg yolk and three parts whipping cream.
2. Temper the egg yolk and cream mixture by adding a small amount of the hot liquid while stirring.
3. Add the warmed liaison to the remaining hot liquid. Plain egg yolks coagulate at temperatures between 149 and 158 degrees F.

With the food thickening agents described above, and a few good sauce recipes, you should now be able to turn out a pretty good sauce.

And, don't worry if you first few attempts aren't all that great. There is a small learning curve. But I promise, your sauces will get better and better with practice. (My first sauce attempt was an unmitigated disaster - I don't want to talk about it.)

Sauces Finishing Techniques Favorite Sauces Other Sauces

	Web How To Cook Gourmet