Why do light and dark roux have different effects when thickening sauces?
When you are using a roux, the darker it is, the less it acts as a thickening agent in a sauce and, vice versa, if the roux is quite light, it has more of a thickening effect.
Why is this?
Best Answer
You can visualise it like this: starch is the way that plants store energy, you can see it like long chains of glucose molecules. If you have these long chains, they lock in water at high temps (gelatinisation), and so they bind sauces. If you burn them, what you do is break those chains into glucose (or maltose), and that glucose you caramelise..that is what makes it brown...and the proteins are in the Maillard reaction..that is "caramelising" of proteins instead of sugars, but that is less relevant for the binding power of starches. So, you are breaking and burning the chains that you need to catch water, basically. (and please do not correct this text from UK to US spelling, thanks...)
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What is the main difference between a light and dark roux?
Roux are always cooked to a specific shade that can range from white to blond to peanut butter\u2014and even darker. The darker the color the more pronounced the roux's flavor. But at the same time that a roux darkens, its thickening power lessens.Does darker roux thicken less?
Dark Roux. Dark roux is the darkest, it has a dark nutty color and has a very complex flavor. It also thickens the least amongst the white and blonde rouxs.Which color of roux has the most thickening power?
Like stated above, a lighter roux has more thickening power, while a darker roux has more flavor.What does the color of a roux depend on?
Rouxs change character and color depending on how long they are cooked. A light roux is cooked until bubbly and the starchy flour taste has gone. A blond roux is made with butter and cooked until the mixture turns a beige color. Both are used to thicken white or cream sauces or light soups.Roux and Mushroom Gravy
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Answer 2
The primary thickening agent in flour is the starch. The browning of Your roux is a chemical reaction that uses up starch that can be used to thicken to make delicious ness.
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