Nougat Science
You can now purchase my handmade candy bars and marshmallows at http://www.bonbonbar.com/
I’ve been battling a bit with nougat this week, and this post is going to go into quite a few corners of confectionery esoterica — into the areas of boiling sugar and using glucose. I can only imagine that Alton Brown would be riveted…
Nougats such as Montelimar and torrone are traditionally honey-flavored confections made by whipping boiled sugar/honey/glucose/corn syrup-based syrup into egg whites. Nuts and dried fruit are often mixed in for flavoring and texture. (Side note: whipping sugar syrup into egg whites is also a technique used to make Italian buttercream frostings and some kinds of marshmallows; the differences lie in the temperature that the syrup is boiled to, the ratio of sugar syrup to egg whites, and what else is added– lots of butter for the frosting and corn syrup or glucose/gelatin/vanilla extract for marshmallows).
Anyone who’s eaten a Snickers, Three Musketeers, or Milky Way knows that those nougats have nothing to do with honey or chopped fruit. And I’m okay with that… b/c I’ve been aiming for a fruit puree-based nougat and a mint nougat. I want my nougat to be flavorful and fluffy without being too chewy, and I’ve had these criteria in mind:
- I want my nougat to be free of high fructose corn syrup, so I’m avoiding Karo corn syrup. Glucose is my substitute of choice b/c it doesn’t taste too sweet, it doesn’t contain high-fructose corn syrup, it doesn’t attract too much moisture, it inhibits crystallization like other liquid sugars, and it’s relatively inexpensive. Glucose has an industrial-sounding name, but it’s just a molecular form of sugar that can be derived from corn, wheat, and other substances; one tub of glucose that I had listed one ingredient: corn syrup. Granulated sugar is sucrose, which is a disaccharide composed of glucose and fructose. So while Karo goes the (high) fructose way, I go the glucose way. For some reason that I wonder about, glucose is not commonly found in stores. If you’ve never used it, know that it’s extremely thick and sticky — much more so than honey or corn syrup. Consider that this means that it contains less moisture than honey or corn syrup.
- I want it to taste like fruit or mint, not like sugar or honey.
- I want the flavors to taste fresh, so I don’t want to use fruit or mint flavor extracts. The mint nougat should contain some form of mint leaf. The fruit nougat should be made from fruit, either juice or peel.
And you know what? I haven’t found a single recipe online or in cookbooks that has met my criteria. That’s fine, since, of course, I am developing my own recipes, but I have to start somewhere, so I’ve been looking to adapt recipes. Usually, what I have to do is figure out (1) a way to incorporate fruit liquid (b/c fruit juice or puree is not as concentrated as extracts, although they can be reduced to produce more flavor per amount of liquid), (2) how to substitute glucose for corn syrup and (3) what temperature to boil my sugars to.
Boiling sugar. This is where it gets fascinating… and tricky. If you put a layer of sugar on the bottom of a pot and put it over heat, it’ll melt and caramelize quite rapidly; sugar reaches the caramel stage btw 320F-350F. It will color and when cooled, will be brittle and have a caramel flavor. This is the dry method of caramelization, which is something like gunning your car straight from 0-60mph in 6 seconds flat.
But, if you add water to the sugar and put it over heat, you can track the sugar gradually going through all of its stages, such as thread, soft ball, hard crack, etc.
What I find so interesting is that the temperature of the sugar will not increase until its water content decreases. So, when you use this wet method, it’ll usually heat up to a little under 220F and hang out there for a while until enough water has boiled out of it for it increase, which it will do pretty rapidly. According to Jean-Pierre Wybauw’s book Fine Chocolates, Great Experiences, a sugar syrup at 219.2F has a water content of 35%. At 221F, it has a water content of 30.6%. In the difference of only 1.8F, it has 4.4% less water! When it has reached the thread stage (which begins at 230F), it has 19.1% water. And so on, it progresses. Wybauw’s chart goes to 266F (the end of Hard Ball), at which point the syrup solution has only 4.9% water. When it finally caramelizes, the water is boiled off… so it can wind up just like the dry method.
So, knowing the % of water supports what the names of the sugar stages and temperatures intuitively tell you — as they get higher, they have less water to lend flexibility… hence, they get harder and more brittle. You’ll notice that the syrup thickens as the temperature increases by the way the bubbles act, but it has to cool for you to see how hard it will be (you can either pour it out and wait or drop a little in cold water for a quick test).
But… if only it were that simple… if only mastering this concept would allow you to master nougat-making. I consider there to be at least four factors that further complicate all this in regards to nougat:
- the type of sugar that you use - do sugars other than granulated sugar (such as corn syrup and glucose) have the same properties at the same temperatures? Almost all candy recipes contain liquid sugars in addition to granulated. A corollary issue — what proportion of each sugar should you use? Most nougat recipes are a combination of glucose/corn syrup/honey and sugar. And nougat recipes call for boiling to be anywhere from 252-310F.
- what you add to the sugar solution - How much egg whites to use? How much liquid can you use without it ending up all oozy, no matter what you boiled the sugar syrup to (even caramelized sugar–with its very small water %–can be liquefied again by adding enough water/cream/liquid)? How will acidic ingredients affect it?
- the effects of room temperature and humidity - or as I’ll call it, the Cosmos Laughing at You Factor, b/c it seems like even temp/humidity controlled areas can be affected by the rain outside.
- the effects of time on texture - sugar can have a way of sort of re-crystallizing over time, which can be great if you can predict it for a desired texture. Whether or not it is enrobed (that is, sealed off from air) is also a factor in this. Some nougats are supposed to be left out overnight, and some are supposed to be enrobed right away. As I read in Emperors of Chocolate, the Milky Way nougat takes two weeks to reach its preferred texture — under what conditions is it left for two weeks, and why does their formula take two weeks for the texture to come about?
So, I looked around in books and online and formulated a sugar syrup that was about 1 parts granulated sugar to 2 parts glucose, and enough water to moisten it; I wanted it to be chewy and moist, without much recrystallization. I boiled it to 252F, and was able to make a nougat out of it that was nice — soft and melting… perhaps a little bit too much so.
For subsequent trials, I decided to boil it higher, to 275.
And this is where it all fell apart.
The syrup wouldn’t incorporate into the beaten egg whites. It hardened into twigs of all size within the beaten egg whites and stuck to the whisk in a gelatinous, quickly-hardening clump. I thought it was a fluke — I’d never had this happen before with any of my “sugar-syrup-into-egg-whites” applications. Maybe the egg whites were too cold (which was unlikely, since they’d experienced all the friction/heat that it takes to whip them to medium peak)… Maybe I’d poured the syrup too much onto the whisk and it had cooled down… Maybe the syrup was too hot and should stop bubbling completely before being added to the egg whites… Maybe the syrup had cooled too much…
I tried again. The same thing happened. Sugar twigs in whipped egg whites. Some of the syrup had hardened onto the side of the bowl, before it had even reached the egg white.
So, I went back to the nougat recipes and looked again at their formulations. The one I’d primarily based it on had used a lot of corn syrup and a little bit of sugar. Other recipes, that used glucose to begin with, used almost equal amounts of glucose and granulated sugar.
And I believe that to be the difference. Glucose boils up differently than sucrose and corn syrup; it is after all, much thicker at room temp to begin with. The % of moisture in the Wybauw chart only applies to granulated sugar. In this case, I guess that the large amount of granulated sugar in relation to the glucose thins it out to a degree — a degree that the thinner corn syrup does not need. I had decreased the quantity of glucose from the original amount of corn syrup called for, in an attempt to compensate for the denser-seeming glucose, but that hadn’t been enough.
I now also wonder, though, how the percentage of liquid sugar in a sugar syrup affects the stage that the sugar is at at a given temperature. For instance, at 244 (”firm ball”), how will a sugar syrup with, say, 1 parts corn syrup to 2 parts granulated sugar differ from a sugar syrup with 2 parts corn syrup to 1 part granulated sugar?
So, anyway, for this nougat I was working on, I increased the ratio of sugar to glucose in my recipe until they were almost equal, fired up my stove and mixer once again… And it all incorporated beautifully.
And now I’ll be back at it again, to refine taste and texture…
Edit: McGee says that glucose caramelizes at 300F. I think that explains at least a bit.

