Thursday, November 5, 2009

To cook or not to cook (roux vs. beurre manié)

The difference between roux and beurre manié has bothered me for years. Both consist of 1 part flour to 1 part butter. Both are used to thicken liquids. But roux is cooked in a pan for a few minutes over relatively low heat while whisking and beurre manié is mashed in a bowl with a fork until it forms a smooth paste (you need butter at room temperature for that).

Making roux is one of those culinary rites of passage, which I found strange because I thickened sauces happily for years with no roux. The first sauce I learned to thicken about 10 years ago was a cream sauce for poached fish from Julia Child's Mastering the Art of French Cooking. It called for thickening with beurre manié, which was so incredibly easy, reliable, and delicious that I used that method whenever I needed a thickener. Eventually, I found out that beurre manié is supposed to be a lazy way of thickening. One should cook the flour and butter first to "cook out the flour taste." Even Julia herself said that in one of her shows.

There was a good discussion of beurre manié and roux on Michael Rhulman's blog, where no one seemed to agree on anything (these were mostly professional chefs, so I assumed they knew what they were talking about). Some people claimed that if roux is not made with clarified butter, it has less thickening power. Others claimed that sauces thickened with beurre manié would thin out after several minutes of simmering, particularly if you double dip when tasting since your saliva contains a starch digesting enzyme. Proteins, enzymes, catalysts, and other big "sciency" words were summoned to give more weight to the arguments that seems quite empty to me.

Cooks are funny people. They have this awe of "food science." If Alton Brown or Harold McGee said something with the word "protein" in it, it seals the deal. After all, science is always right. Well, that's not really science to me. That's just regurgitation of something someone said. Real science is all about setting up a proper experiment with good controls and that's what I decided to do to answer this thickening question once and for all.

I made 4 sauces:
  • bechamel with roux
  • bechamel with beurre manié
  • velouté with roux
  • velouté with beurre manié
The liquid in bechamel was whole milk. The liquid in velouté was chicken stock. Here are some parameters that I kept the same:
  • same pot
  • exactly the same amount of liquid, flour, butter (I didn't clarify it), and salt
  • same simmering duration (3 minutes after combining hot liquid with flour/butter)
Well, I tell you what folks. I don't know about proteins and enzymes, but there was no discernible difference. Beurre manié thickened sauces didn't have any unpleasant flour taste. They were just as smooth and just as thick as roux thickened sauces. Out of curiosity, I continued to simmer them while intentionally double, triple, and even quadruple dipping my spoon to test the hypothesis that continued simmering or saliva can thin out beurre manié thickened sauces. At some point I wondered if I should just spit into the pot (don't worry, I wasn't going to serve these sauces to anyone ;). Well, no thining out happened. If anything, the sauces got thicker due to more water evaporation.

This sealed the deal! Beurre manié wins. I am a one pot kind of girl and roux requires a whole other pot, so that you can cook your flour/butter. Beurre manié requires just another little bowl and a fork, which can easily go into the dishwasher.


Anonymous said...

I too have wondered about that "nasty raw-flour taste" that Juia and others have described, and I too have never discerned it. I even have been known to shake up flour and water in a jar and add it to stews to thicken them, with no unfortunate taste results. Sometimes we have to rely on our own brains and experience.

Nessa said...

Thank you for your little experiment and post. It was very helpful to me!


Stephanie said...

I learned to make roux in Home Ec. class. I’ve never tried making beurre manie - but I'm going to now. The best meal of my life was beurre blanc on halibut at Mangia Pasta in Bend, Oregon.

Carla and Michael said...

Great post. I just made a recipe that called for buerre manie and it waws a first for me. Liked the idea very much and will use it in future recipes. I think the only time you need to make a roux is when you want it to be dark like in gumbo or jamalaya.Have also heard about the flour and water (or any liquid) in the jar. Both easier than a roux. But then they say:to each his own...

Helen said...

about flour and water shaken in a jar... that's a totally legit way of thickening and is called a slurry. Works great for stews where you are not looking for the thickener to add richness. In sauces, you usually need a little richness as well. that's where beurre manie comes to the rescue.


Tom said...

Thanks for the experiment! As a chemist I highly value the testing of ideas. It's well and good to have a theoretical framework and explanation, but almost all scientists with a lab know that in a complex system, which food most certainly is, you must always test, ideally in multiple ways, to cover all the bases.

I can see a few remaining uses for roux:

- If you want a darker roux to add some flavor.
- If you do not have any butter at room temperature, it's about as easy to do a tiny saucepan of roux as to attempt to microwave the butter
- If you are going to be making the sauce all in one pot anyway, it's easy to start with a roux.

Great post as always.

Helen said...

Hi Tom,

Great points! About microwaving the butter to soften it... it doesn't work as it will melt it in parts. That is one draw back on beurre manie. Since I usually only need 1 Tbsp of butter for it, I cut it into 4-5 slices and it becomes mashable in about 5 minutes.

About one pot... since most of the sauces that require a roux, ask you to add hot liquid, you need to warm up this liquid in another pot (I guess you can also microwave it in something), but I can't think of any roux based sauce that's a one pot deal.

Another thing I don't really like about roux is the necessity to measure you liquid. If your sauce is too thin, you can't easily add more roux (unless you get out another pot and make some more), and if your sauce is too thick and you ran out of stock, too bad. With beurre manie, I always make more than I think I need and add it a bit at a time. Once the sauce is desired thickness, I stop.


AppleC said...

Excellent experiment. Very informative.

Jess said...

Interesting! I'm a roux fan myself, but largely because I like the process. It forces you to slow down and pay attention. I'm not big on measuring and timing, so making a roux means watching and smelling. No matter how stressful my day has been, I'm always nice and centered by the time my roux is ready. Not quite as good as yoga, but in the same vein. :) Still, it's good to know that a beurre manie is an option when I'm pressed for time.

I have tasted the "nasty raw flour taste", in a roux that my husband made without cooking it out (and it was awful!), but, then, he used a LOT of flour (more than a quarter cup), so of course it would be noticeable.

Also, a dark roux is part of the flavor profile of some dishes, notably gumbo. My cousin-in-law from New Orleans has a story about how, when she made gumbo for the first time as she was a teenager, her recipe said to cook the roux until it was "the color of a hazelnut". Instead of guessing or asking someone, she actually went out and bought hazelnuts so she could compare them.

Barbara said...

Thank you for this post - I really appreciate the effort you made to provide this information.

Helen said...

Hi Jess,

Great to hear from you! A brown roux is a totally different story. Since I don't cook Cajun, I've never made one. My comparison was mostly what one should use to thicken pan sauces, gravies, etc.

There are a lot of things that can go wrong when working with either roux or beurre manie that will make them taste bad: wrong proportion of flour to butter to liquid, lumpiness, etc. Sauces with beurre manie are simmered for a few minutes too. So if done correctly, there is not much difference between a blond roux and beurre manie.


Cyn said...

Wonderful post. I love that you busted this kitchen myth. Nothing blowing up as on "Mythbusters" but very interesting -- and much more relevant for someone like me.
Whenever someone instructs me to do something a very specific way in the kitchen, I want to know why.
No sense in extra steps (or extra pots to wash) unless there is a good reason.

Laura [What I Like] said...

That whole raw flour taste thing does seem to be one of those lines that everyone used, and I too wondered if it actually had a discernible taste...thank goodness you've cleared it up for us all! Beurre manie all the time for me's always been my favorite truth be told.

Anonymous said...

Thank you for this experiment. Like you, I am a fan of the scientific method.

But I have tasted that "flour-y" taste and I wonder if it depends on:

1. The amount of roux/beurre manie
2. The type of flour (hard vs. cake)
3. Butter content of the butter.

Hmmm...maybe I'll have to do my own experiment. Right after I solve my current mystery of "the apple crumble that wouldn't brown).


Anonymous said...

Er, that should be FAT content of the butter. Not enough coffee yet!


Helen said...

Hi guys,

I am so glad this topic has generated such a lovely discussion. Let me address a couple of things. First of all, I only had one taster: me :) To do a proper experiment, you'd need way more testers, particularly since taste is a very personal thing. Second of all, there are many problems that can result in the nasty raw-flour taste. One is not getting flour to dissolve well in liquid. If you end up with lumps (even tiny ones), it will taste icky and floury. Another problem is using too much roux or beurre manie. My sauces tend to be on the runny side, but for my experiment, I used the proportions normally used for veloute and bechamel (1 Tbsp butter - 1 Tbsp flour - 2/3 cup liquid).

Anyway, to make a long story short, you need to make sure you use whatever thickener you decide on properly and take my experiment with a grain of salt. Try setting up your own experiment to decide for yourself. It only takes 30 minutes or so.


Anonymous said...

Hi there,

Nice post. However, there's a flaw here that I think you and your commenters are making.

It is true that a roux is a simple method of combining fat and flour. However, when I (and most people, I think) hear "roux," we think of the long-cooked fat/flour combination that is essential to many Cajun and Creole dishes.

You don't think that way, of course. You are looking at roux as something to merely thicken another substance. This is borne out by your statement:


So do you want to know why it is a rite of passage? It's because cooking a darker roux (in a pan, not in the oven) actually does take some patience, skill, and fearlessness. It's easy to burn, requires almost constant attention and exact heat adjustments, and will leave a permanent, nasty scar if you make a mistake.

Of course, those types of roux are not used for thickening -- they are used for color and, most important, flavor.

If you're just talking about mashing up flour and butter raw, or mashing and then just swishing around in a pan for a few minutes -- well, that's minor league, IMHO. That's cool, though -- your post was all about thickening.

But no, that's not a rite of passage, so I would caution you against being too dismissive.

Go make a real roux -- bordering on the color of chocolate syrup -- without burning it. Let us know how that goes.

Because THAT is the rite of passage. ;)

Keep up the great work.

Helen said...

Hi there,

I agree that Cajun roux might be tricky to make and have absolutely no expertise in that cuisine. Since my blog is mostly about european cooking, I was talking about what most european cuisines mean by a roux, which is blond roux. Comparing a brown roux to beurre manie is like comparing apples and oranges. That would be really silly.


Anonymous said...

Thanks. And cooking a blonde roux vs. a beurre manie is comparing apples to apples. Thanks for the wonderful insight.

Anonymous said...

I realize this discussion is old, but other folks had a similar discussion on a different website, and there was some good info

Venus said...

Good thing someone made an experiment and share on this site. It was helpful now I truly understand the difference between the 2 thickening agent and may help me on my upcoming exam in culinary. :)

Anonymous said...

About that bad flour taste: But remember, with all due respect, Julia Child is the one who recommended blanching bacon to rid it of that awful salty, smoky flavor.


Anonymous said...

I don't get the need for a second pan. I have always just made my room in the pan I'm making the sauce in.

Helen Rennie said...

If you want to reduce your stock or drippings before adding them to the roux, you need a second pan.

Aidan M said...

Thanks for your experiment. Saves me the time and answers my very same question as yours. Much appreciated! :-) ..... Roux's retired in my kitchen from now on!

Jim Slaton said...

Forget the flour. Use corn starch. works great. doesn't break down. no flour taste. been doing it for years.

Anonymous said...

Interesting conversation. I am a chef for the past 17 years and had the benefit of working in New Orleans, the home of a dark roux. In this moment i am tipping my hand because i have experienced great rouxs and the love of cooking. You yourself have tipped you hand by saying that you only did beurre manie before. I feel by reading into it that this experiment was done to prove that beurre mane was better. They both have different applications. If you are making a 5 hour gumbo, please use roux. If you are finishing a simple cream or stock sauce for your two pieces of white fish at 8:30 at night for you and your lover, by all means please use a beurre manie. One does not have to be better than the other of from a professional standpoint, to hear someone say beurre manie "wins" over a roux, discredits your cooking knowledge and aptitude from a glance. Great post, great comments. Bonne Chance

Helen Rennie said...

Brown roux used in gambo is a completely different matter. It's role is not just thickening, but flavoring the dish. If the goal is just to thicken a sauce that will be served soon and not saved for the next day, beurre manie works just fine and is faster and easier to work with. The only down side is that if the sauce is saved for the next day, it could thin out a bit, but that's rarely the use case I am dealing with.