Big Batch Bechamel

[bpdetroit]

I need some tips on keeping my bechamel thick when making a big batch. I'm using 2lbs of roux per gallon of milk, a total of 27 gallons per batch. I think my starches are thinning because of too much stirring and maybe too high of a heat after the starch has fully gelled. This is what I have gleaned from McGee.

My questions are these:

Does a larger batch of sauce require a larger amount of roux? In other words, does the ratio of roux to liquid increase as the volume of liquid increases?

Can you make that much bechamel at one time?

Also, does bread flour used in roux thicken better than AP flour?

Any tips would be greatly appreciated.

[Lisa Shock]

AP flour varies in starch & gluten by region. In some parts of the U.S. (generally the NorthEast) it's very close to bread flour in terms of starch and gluten content. In other regions it's very close to cake flour(the South) and in others it's close to pastry flour. You need to get some numbers on your particular producer of AP flour for that answer. Ask for the protein content of the flour, and you'll have the answer.

Generally, for a roux, you want more starch and less gluten, so, I'd avoid bread flour and go for AP or biscuit/cake flour, if available.

It's hard to say about the other ratios because the darker a roux is cooked, the less it thickens and, if it's undercooked it doesn't thicken as well, either. So, how it is cooked affects it a great deal and small changes in procedure can have fairly major consequences. I'd start taking temperatures and timing everything.

[Qwerty]

Starches CAN break down after prolonged cooking, though this is less a problem with flour than with other types of pure starch (arrowroot, corn, etc). Your ratio, if anything, seems high to me, but since it's not enough I don't know what to tell you.

I haven't made bechemel much since culinary school--IIRC, a "proper" ration was 1 lb of roux per gallon. So you should be fine. It's most likely either too high heat or too long cooking, or a fundamental problem with the flour itself, as Lisa stated.

I don't really know what to tell you, unfortunately. Just curious, what on earth are you using 27 gallons of bechemel for?

[Shalmanese]

One POUND of roux? That sounds way too high. If you can get it, Wondra flour is low protein which makes it useful for sauces.

[Chris Hennes]

It's not that high: CIA ProChef's ratio is 1 lb white roux to 4.5 quarts of milk, reduced to 3.5 quarts total bechamel.

[Qwerty]

Yeah, again, I didn't check, but I'm pretty sure the standard was one pound of roux. That's debatable, of course, and up to the individual person making it. And I think that it gives you a pretty thick sauce, but IIRC it's standard.

It's also half of what the OP was using per gallon of milk.

[AAQuesada]

The hardest part of making big batches of bechamel is making the roux properly. Are you using oil or butter for the roux? If you're using butter are you cooking off the water first.. there is a lot of water in 15 lbs of butter. what is the temp of your fat when you add your flour? If it's too high the flour wont properly absorb the fat and you won't get all the thickening you could out of your roux.

1lb per gallon for a med thick roux is how I learned it as well. 2 lbs of roux per gal is way too much, something is wrong if you have to use that much roux.

[bpdetroit]

Thanks everybody. I am going for a rather thick sauce. I'll have to try and dial in the roux. I haven't used Wondra but thanks for the suggestion. A friend of mine suggested moving the project out of the kettle and into the tilt skillet. I'll post once I have the whole thing sorted.

[faronem]

The rule I've always followed for a roux ratio destined to make a sauce consistency is 1lb flour, 1lb butter per gallon of fluid.

I'm guessing that's what you mean by 2lbs of roux per gallon.

I've used this with volumes up to 10gals with no trouble.

I'll add water to offset evaporation to end up with a finished sauce volume equal to my starting liquid.

A few possibilities come to mind.

It is possible you're shocking or breaking the starch in the flour because your butter is too hot when making the roux.

Similarly, if your milk is too cold (it should be scalded) it can shock the flour and prevent thickening.

The sauce would need to come to a full boil throughout after adding in the milk in order to thicken properly.

Are you weighing out the flour (vs. volume measurements)?

After making your 54lbs of roux in a large batch, I imagine you could test a small batch of it (1/4c roux per 1c liquid) to measure its effectiveness.