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If you’ve caramelized sugar before, you might recall there are two ways to do so: the ‘dry’ and the ‘wet’ method. The only difference being the presence, or absence, of water. Both work fine and turn your previously white sugar into a brown liquid full of flavor and smells.
Is one method better than the other? Does it even matter? We’re going to find out!
- Caramelization turns sugar brown
- How to caramelize sugar
- Comparing 'wet' caramel vs. 'dry' caramel
- Troubleshooting sugar caramelization
- In the end, it's mostly a personal preference
Caramelization turns sugar brown
During caramelization you’re turning sweet, white sugar, into a brown, almost bitter, product: caramel. Once the sugar is hot enough, a series of chemical reactions kick in which turn it brown and change its flavor. Continue for too long and the sugar can burn, turning black and bitter. These chemical reactions are jointly referred to as “caramelization”. And really, there’s only one thing you need to make it happen (aside from sugar): heat.
Caramelization needs heat
Just how much heat you need depends on the type of sugar you’re trying to caramelize. Regular cane or beet sugar is made up of a molecule called sucrose. Sucrose starts to caramelize around 160°C (320°F), and the same applies to glucose. Fructose, which is common in fruits and honey, caramelizes from about 110°C (230°F). Maltose, which you can find in grains, needs significantly higher temperatures to get going, 180°C (356°F).
|Sugar||Caramelization temperature (approx.)|
|Glucose and Sucrose||160°C (320°F)|
Interested to learn more about the chemistry of caramelization? Want to learn all about the chemical reactions taking place? Read our deep-dive.
An aside on sugar caramel vs. caramel candy
Note, when we talk about caramel in this article we refer to: “sugar that has been caramelized”.
How to caramelize sugar
In summary, to make caramel you need to heat just sugar. There are roughly two methods to do so:
- the ‘wet’ method: uses water to dissolve the sugar, before starting the process;
- the ‘dry’ method: does not use water and caramelizes sugar directly.
Caramelizing using the ‘wet’ method
To caramelize sugar using the wet method you start by adding both sugar and (hot) water to a pot. You’ll want to add enough water so all the sugar can easily dissolve. You’re then left with a transparent sugar solution and no more individual sugar crystals.
Next, you’re going to boil this sugar solution, until it starts to caramelize. Since a liquid is better at transferring heat than solid particles, it tends to be quite easy to evenly heat a solution. You might have some parts that heat up a little faster than others, but different should be minor. This helps to prevent that part of the sugar burns, before other parts have had a chance to turn brown.
However, all that water does prevent the sugar from getting hot enough to caramelize. The water serves as an ‘insulator’. As such, you’ll have to evaporate the water again. You do this by simply continuing to heat the sugar solution. More and more water will evaporate. As that happens, the temperature of the sugar solution will go up as well.
Once almost all the water has evaporated sugar starts to turn brown. This happens around the caramelization temperature. Continue heating until the caramel has reached the desired color and take it off the heat immediately. It will continue heating up for a little while though, so best to immediately pour it onto a heat-proof surface or use it for your application to prevent it from turning any darker, you wouldn’t want burnt caramel. We’ve found that it’s very tricky to measure temperature at the end, so even though we’re big fans of using a candy thermometer when making candy, here it’s best to trust you senses.
Best to do it reasonably fast to prevent crystallization
One of the most common ways for sugar caramelization to fail is because sugar starts to crystallize. This can happen once the amount of water in the caramel gets low. We found that the best way to prevent this from happening is to boil the wet caramel at a reasonably high heat. It keeps on moving and bubbling and we’ve had very little crystallization happen this way. Also, be sure to refrain from stirring once all the sugar has dissolved! There’s no use in doing so, you can only induce crystallization.
Some recipes will tell you to wash away any sugar crystals that form on the side of the pan when caramelizing sugar this way. However, we’ve found that messing around with it too much only increases the chances of crystallization. We’d recommend to just let it do its thing quickly, and leave it alone.
Caramelizing using the ‘dry’ method
The alternative to the wet method is the dry method, which does not use any water. Instead, you simply add sugar to a pan and heat it up. Since there is no water, the sugar won’t dissolve. Instead, the sugar will melt* once it’s hot enough which is well above the boiling point of water. Once molten, the sugar can start to caramelize quite quickly since there is no water that needs to evaporate first.
How to melt sugar
However, it can be tricky to ensure even melting of sugar. Solid sugar crystals aren’t great at transferring heat among themselves. If the pan or stovetop you’re using heats unevenly, some parts may start to brown before other parts have even started to melt!
*Note, scientists have been discussing whether or not sugar actually melts during this process. Refer to the article by Roos (2012), quoted below, to learn more!
Use a blow torch
There is another way to caramelize sugar without using any water: using a blow torch. However, it’s only suitable for small quantities, in special circumstances. The intense, but very local burst of heat can easily heat sugar sufficiently to start caramelization. This is what’s used to make the crispy sugar layer on top of a creme brulee for instance.
Comparing ‘wet’ caramel vs. ‘dry’ caramel
Both the ‘wet’ and the ‘dry’ method can be used to caramelize sugar and produce a similar result. But, there are some differences that may make you choose one over the other.
‘Dry’ makes a darker caramel, or not?
When comparing the ‘dry’ with the ‘wet’ method, we noticed that the ‘dry’ method consistently made for a darker caramel! This happened even when we tried to heat the caramels to the exact same temperature! What happened?
To investigate, we need to have a closer look at the chemistry of caramelization. Remember that caramelization is a series of chemical reactions. At first, the small sugar molecules themselves undergo small changes. Later on, the resulting small molecules will all react together to form large brown molecules. It’s a very fast process, but also quite random. A lot of reactions happen simultaneously.
The reaction solely relies on the presence of sugar. Water does not play a significant role. We found no evidence that the water could change the course of chemical reactions that occurs.
Hot spots get a head start
Instead, we expect uneven heating to be the culprit.
When using the ‘dry’ method it can be hard to ensure all sugar is at the same temperature. Some parts of the pot may be hotter than others. This can cause some of the sugar to caramelize before other sugar crystals had a chance to melt. Once the pot as a whole has reached the target temperature, some of these hot spots may have already turned a dark brown color. As a whole, the final caramelized sugar will be darker in color.
Aim for color, not temperature.
To overcome this challenge: aim for a color, not a temperature. Caramelized sugar changes color very quickly. Getting a consistent, even temperature measurement can be very tricky, especially for small batches. Instead, judge a batch by its color. It will be more predictive of its final color and flavor.
You might find this confusing, seeing as how we do strongly recommend cooking sugar syrups with a thermometer at hand! However, keep in mind that all caramelized sugars are already very very hot and have an almost identical moisture content. A few degrees more or less won’t make as much of a difference anymore.
‘Wet’ takes longer, thus is browner? (No!)
You may often find statements online saying that using the ‘wet’ method will make a browner caramel since it takes longer to make. However, as you could just see, this is not true. On the contrary, chances are the opposite happens!
Keep in mind that the time that you spend boiling off water is NOT used to caramelize the sugar. Sugar only starts to caramelize way at the end. Not a lot happens before that time.
Except if you make A LOT of caramelized sugar
Of course, there is an exception. That is if you make a lot of caramelized sugar. So much so, that it’s on the stove for an hour before it even starts to caramelize. During this time, sugar may start to break down and influence the caramelization process.
‘Dry’ is faster
If you don’t have a lot of time to caramelize sugar, use the ‘dry’ method. Since you don’t have to boil off the water, it’s considerably faster.
Use a thermometer with alarm to speed up ‘wet’
Want to use the ‘wet’ method and not stare into a pot of boiling water for a long time? Place a reliable thermometer with an alarm in your sugar solution. Have the thermometer start beeping several degrees – give yourself enough time! – below the caramelization temperature of your sugar. (Best to run a few tests batches to define this temperature.)
Still, never walk away completely, stay close. Sugar caramelization goes incredibly fast at the end and before you know it, your well-kempt sugar has burnt and turned a solid black!
‘Wet’ is more foolproof
Never caramelized sugar before? Use the ‘wet’ method to get the hang of it. Having water there as a helper makes it easier to caramelize sugar evenly.
You can start over and over and over
When using the wet method, you run the risk of sugar crystallizing while you’re boiling it. When this happens, large sugar crystals form in the pot during boiling. To prevent this from happening, refrain from stirring and mixing. This can induce crystallization.
If it happens, don’t stress out! Just add a little extra water – be careful, it may splatter! – and start over. You can easily do this a few times if necessary.
Trying to make caramels and running into crystallization issues? We’ve got a separate post to help you out with common caramel making challenges.
‘Wet’ allows for steering the reaction
Caramelization reactions can proceed differently depending on the acidity of the environment. If the sugar is in a very acidic, or very alkaline (= opposite of acidic) environment, the reaction can proceed very differently.
Using the ‘wet’ method makes it easier to make these adjustments and thus control your final caramel color.
We’ve written a more in-depth analysis of this phenomenon.
Troubleshooting sugar caramelization
Even though caramelizing sugar isn’t that complex, it’s still to mess it up. Since you’re working with very hot, sticky, troubleshooting may seem daunting. Luckily, there are a few things you can do, some of which we alluded to above.
Fixing sugar that has crystallized during caramelization
It’s the fear of many candy makers: a pot full of sugar crystals. Whereas just a short while back your transparent sugar solution was boiling along well, it turned solid in seemingly just a few seconds. It doesn’t make sense to continue to hear this mess. You’ll burn the bottom, without ever properly caramelizing the top.
To fix this problem, you do not need to throw it out. There’s a fix. So let’s have a closer look at what happened in that pot.
Sugar loves to crystallize
That large mass in your pan is sugar that’s turned crystalline. Sugar, or sucrose more specifically, has a strong tendency to crystallize. When there’s not enough water available, the sugar molecules will form a crystal. This can happen as you’re caramelizing sugar, especially in the wet method.
Remember that you’re evaporating more and more water from the sugar solution you made at the start. The concentration of sugar becomes higher and higher. As look as you continue heating and leave it alone, that’s not a problem.
However, if you turn off the heat, or turn it too low, the sugar solution becomes unstable. That same can happen when you stick something into the solution or quickly stir the solution. The sugars start to crystallize and this can go very rapidly!
The fix: Dissolve the crystals again
Luckily, you can easily reverse this. Simply add extra warm water. Once enough water is present, the sugars will redissolve. It may take a little while to dissolve all the crystals, and you may need to heat it slightly. But, the sugars will redissolve and you can continue caramelization.
Can you caramelize brown sugar?
Slightly off-topic, but a commonly asked question. Can you caramelize brown sugar?
No, you cannot caramelize brown sugar. Keep in mind that when we talk about brown sugar, we’re referring to the slightly sticky, clumpy brown sugar. This is sugar that has some molasses added back into it. Slightly unrefined cane sugar may also have a light brown color. However, here you’ll clearly see that the crystals are still separate and free-flowing. This sugar will work perfectly fine when caramelizing!
In the end, it’s mostly a personal preference
Both the ‘dry’ and the ‘wet’ methods can make caramelized sugar. One might be easier to troubleshoot than the other. But, both can give you the same product. In the end, whichever you prefer is mostly a personal preference!
Yrjö H. Roos, Felix Franks, Marcus Karel, Theodore P. Labuza, Harry Levine, Mohamed Mathlouthi, David Reid, Evgenyi Shalaev, and Louise Slade, Comment on the Melting and Decomposition of Sugars, Journal of Agricultural and Food Chemistry 2012, 60 (41), 10359-10362 DOI: 10.1021/jf3002526, link