The (small) miracle of béchamel sauce


The (small) miracle of béchamel sauce
Making a béchamel sauce is going to confront you with a little miracle that happens every time: You pour milk over a roux, it's very liquid, you stir over a low heat, and then all of a sudden, miracle, the sauce sets, it thickens, you've got your béchamel.

Let's see what happened.
8,860 4/5 (4 reviews)
Grade this page:
Keywords for this post:SauceMethodPrincipleExplanationStarchTemperatureRouxConsistencyBéchamel
Last modified on: August 27th 2024
For this post: Comment Follow Ask me a question Send to a friend
The (small) miracle of béchamel sauce

A basic sauce

louis bechameil

Béchamel is one of the staple sauces of French cuisine, found in a host of recipes. Its name comes from Louis Béchameil, who was maitre d'hôtel to Louis XIV.
Making it is quite simple: first a "roux" mixture of flour and butter, which is heated and colored (hence its name).

roux


Once the roux has reached the right color, cold milk is added, the mixture is very liquid, and you continue to cook and stir over low heat until it thickens (you'll find the full recipe here).
But why does it thicken? As you'd expect, there's no magic involved, just a little physics and chemistry.

Flour and starch

The secret lies in the roux's flour, which contains grains of starch, a complex sugar made up of glucose molecules rolled up into tiny little balls.

amidon

When the milk is added to the roux and heated, the temperature of the mixture gradually rises.
It's around 70°C that the magic happens: the grains of starch in the flour break up into smaller grains, starch molecules that begin to absorb the milk around them, up to 20 times their volume, thus increasing the sauce's viscosity.

This process, known as starch gelatinization, takes place between 70°C and 85°C, giving béchamel its characteristic thick, creamy consistency.
Note in passing that this process of starch gelatinization is also at work in, among other things, crème pâtissière or flan, where flour is often replaced by maïzena, a corn starch.

In short: Béchamel thickens because it contains flour that is heated, causing its starch grains to burst and absorb the milk around them.
So béchamel is not just a culinary classic, it's also a little chemistry lesson in action.

Lasts posts
XO Cognac Explained: Meaning, Aging, and Flavor Profile
XO Cognac Explained: Meaning, Aging, and Flavor Profile
XO Cognac always goes beyond the labels on the bottle: it is often associated with tradition and quality. You get to appreciate the artistry, character and ageing process when you understand what defines this smooth Cognac. The section below tackles everything about XO Cognac, from complex flavour...
January 28th 2026196 Sponsored article
Butter vs. grease
Butter vs. grease
We often read in a recipe where a pastry is put into a mould that, just before pouring, the mould should be buttered or greased. But what's the difference between these 2 terms?
December 1st 20252,3275
Getting out of the fridge early
Getting out of the fridge early
Very often when you're cooking, you need to take food or preparations out of the fridge, to use them in the recipe in progress. There's nothing tricky about this: you just take them out of the fridge and use them, usually immediately, in the recipe. But is this really a good method?
November 24th 20251,5315
Who's making the croissants?
Who's making the croissants?
When you look at a bakery from the outside, you naturally think that in the bakery, the bakers make the bread, and in the laboratory, the pastry chefs make the cakes. It's very often like that, with each of these professions having quite different ways of working, but sometimes there's also one...
November 23th 20251,390
Oven height
Oven height
When we put a dish or cake in the oven, we naturally tend to put it on the middle shelf, and that's what we usually do. But in some cases, this position and height can be a little tricky, so let's find out why.
October 8th 20254,3635

Other pages you may also like
Sugar syrups
Sugar syrups
In cooking, and especially in pastry, we often use sugar syrups, a simple mixture of water and sugar in varying proportions. Here is a presentation of their differences. .
January 17th 202312 K4.8
No need to boil gelatin
No need to boil gelatin
Gelatin is a magical ingredient for making light, creamy, structured desserts, yet it's often misused in the kitchen. A common mistake in some recipes is the idea that it needs to be boiled for it to work properly, but this is a mistake indeed: gelatin melts at a much lower temperature, around...
November 21th 20248,8765
The 3 kinds of meringue
The 3 kinds of meringue
Meringue – what could be simpler? Just beaten egg whites with sugar added. This makes a fairly stiff mixture which can then be cooked in a cool oven to create those lovely, light confections. But in the world of professional patisserie, meringue comes in three different kinds. Even if the...
June 14th 201365 K4.5
Raising (or leavening) agents
Raising (or leavening) agents
When we want to make a dough or batter rise when baking, either in patisserie or bread-making, we need to use a raising agent or leavening agent, one of which is called leaven. In the context of baking, a raising agent is simply what "makes something rise". It is a substance which, when added to...
June 16th 202157 K4.8
The golden-brown finish on puff pastry
The golden-brown finish on puff pastry
Let's take a look at the tricky matter of producing puff pastry with an attractive, golden-brown finish. French pastry chefs call this "dorure" (literally, "gilding"). Behind this quirky term there lurks a real problem (and the solution): when using puff pastry (pâte feuilletée) for a pie, or...
February 8th 201848 K 24.6
Post a comment or question
Posted by:
I am not a leaving thing

Follow this page
If you are interested in this page, you can "follow" it, by entering your email address here. You will then receive a notification immediately each time the page is modified or a new comment is added. Please note that you will need to confirm this following.
I am not a leaving thing
Note: We'll never share your e-mail address with anyone else.
Alternatively: you can subscribe to the mailing list of cooling-ez.com , you will receive a e-mail for each new recipe published on the site.

Back to top of page