In the two-thousand-plus year history of home candy making, there have been only two great leaps in technology: the first was the leap from judging sugar concentration in syrup purely by physical operations like making actual balls and threads to judging sugar concentration by using a thermometer, and that leap technically came in the 13th century.
During the 19th century, candy thermometer design changed very little, with one or two designs basically becoming standard. However, technology has advanced beyond those early thermometers, and with those technological advances has come a shedding of the original design, representing the second great leap forward—digital candy thermometers.
Stellar candy-making results can be achieved with the improved usability, hyper accuracy, and fast-reaction time of ThermoWorks digital thermometry.
The Problems with Traditional Candy Thermometers
The classic candy thermometer with the glass pipe attached to a metal frame had its day. But the truth is, it has many problems:
- It is slow to come to temperature.
- It is inaccurate and falls out of calibration.
- It is hard to read.
- It can attract steam and splatter making it even harder to read.
- It clips in place, only measuring the temperature of your syrup at one location in the pot.
Those problems are bad enough, but the last two seal the deal.
- The glass can actually break and spoil your whole batch.
Anyone who has ever had this happen to them knows this is not a trivial matter. And, perhaps, most importantly…
- The many sharp edges, nooks, and crannies on a traditional glass thermometer can easily cause seed crystal formation!
Serious pastry chefs and candy makers know to carefully wash their pots before cooking sugar, because little chips of dried food or scratches or even dust can be enough for sugar crystals to grab hold and turn your whole batch grainy. The same is true of the many crevices and sharp edges of traditional candy thermometers. They can actually increase the chances that your batch goes bad.
With all of these problems, it’s a wonder people still use these old candy thermometers. The happy news is that there is a better way.
4 Things to Consider When Purchasing a Candy ThermometerThe Best Candy Thermometer
The Thermapen is actually the perfect candy-making tool and we recommend you use it in place of the classic candy-monster. Here’s why….
- Accuracy: The margins of victory are slim in the candy world. The difference between the “Firm Ball” stage and the “Hard Ball” stage, or between “Hard Ball” and “Soft Crack” is literally one or two degrees. Defeat often lurks only a few seconds away when cooking over medium-high or high heat. Standard alcohol thermometers (please never use an actual mercury thermometer) can be inaccurate, with small, sometimes imperceptible bubbles forming in the fluid over time. The best digital candy thermometer, Thermapen® ONE is accurate to within ±0.5°F (0.34°C) throughout the entire candy-making range, and you can set it to show tenths of degrees. That kind of accuracy can allow you to fine-tune your caramels and other candies to get perfect results every time. And if you like your caramels firmer or chewier, you can actually control at which side of the tight candy-making temperature windows you stop boiling your sugar with the accuracy of a Thermapen. Plus, mechanical thermometers need frequent calibration, whereas the thermocouple in a Thermapen is exceptionally resilient to thermal and physical shock, almost never needing calibration over the life of the instrument.
- Speed: If you’re concerned about not having a constant reading on your old clunker, concern yourself no more! With speeds of 2-3 seconds per reading and near-real-time updates in temperature changes, the Thermapen is as close to instant as you can get. Receive up-to-the second accurate information without having to mess with pot clips or hot pan walls.
- Geometry: Don’t panic, there will not be a quiz. By geometry, we mean the shape of the thermometer. As we said above, a classic thermometer has lots of edges and nooks and crannies for sugar to seed in, turning your grandma’s fudge recipe into a stiff block of chocolate chalk. The Thermapen’s tiny cylindrical probe has no such hiding places for sugar. And, after you take the temp of your syrup, you can easily wipe the probe off with a damp towel, preventing seeding on your next dip.
- Mobility and strength: A candy thermometer clipped to the side of a pot is not telling you the whole story; it is telling you one tiny part. The business end of such a thermometer is only in contact with one area of your syrup. If you have uneven heat on your stove—and I bet you do!—you could have over- or under-cooked syrup elsewhere. And if you try to stir the pot with your old thermometer, you risk hitting the shaft and breaking glass into your divinity. This isn’t so with a Thermapen. You can freely stir your syrup with the probe tip of the Thermapen, taking super-fast readings all over the pot. And if you hit the side of the pot, well that doesn’t matter at all.
For those who feel unsure about committing to a Thermapen, we recommend the ThermoPop®. Its ±2°F(1°C) accuracy is still tight enough for candy work, and it can also be used to stir through the whole pot for a better understanding of the temperature.
Our Recommended Chocolate Thermometer
For chocolate work, we recommend the ChefAlarm®. While traditional candy thermometers are less critically inadequate for the task of measuring chocolate temperatures, they still fall far short of the mark.
When tempering chocolate, maintaining a narrow temperature range is of utmost importance, which means constantly keeping one eye on your chocolate temperatures, even while you are dipping or enrobing your candies with chocolate—no mean feat. Also, as previously discussed, their accuracy is a problem.
By setting alarms on your ChefAlarm when making chocolate, you free up your attention to focus on your chocolate work even while you ensure that your readings are accurate. The ChefAlarm has a high-temp alarm and a low-temp alarm that you can set to sound if your chocolate starts to creep out of tempering range. The ±2°F (1°C) accuracy is also something you just don’t get with standard candy thermometers. Keep both eyes on your dipping, and let the thermometer watch the temper.
As a final thought, I’d like to leave you with this. Not only is your grandma’s candy thermometer an outdated, inaccurate piece of 19th-century technology, but it’s also a unitasker. You can never use it to check how rare a steak is, at what temperature your bread is rising, or if your Thanksgiving turkey is done properly. A modern, high accuracy thermometer can improve not only your candy making, but everything else you cook, as well.
Knowledge brings control in the kitchen, and Thermoworks has the tools to give you the knowledge you need to take control of your cooking.
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Ken says
I bought the Chef Alarm for roasting, but it has led me into candy making, including allowing me to revive some treasured family recipes that had been gathering dust. My neighbor now calls me the caramel meister.
Martin says
Ken,
That’s fantastic! I’m glad we could be a part of reviving your family traditions. Good cooking!
Richard Ault says
Can I use my Dot for making maple syrup, 219°, or do I need a different probe to monitor temp.
Martin says
Richard,
The DOT is perfect for that work. Go for it!
Richard Ault says
So the standard probe that came with the Dot is alright to use for monitoring the temp.
Martin says
Richard,
Yes, absolutely. The only foreseeable problem would be its length, but if it can reach your candy, it’s good to go!
Johanna says
Can I use the Chef alarm for chocolate and candy making or is it best to get both?
Martin says
Johanna,
It is best to get both, but you can certainly use the ChefAlarm for both if you have it already. There are slight problems with the ChefAlarm for candy making, but it can certainly work…it’s just not the BEST.
Pamela Grove says
Talking candy thermometers here. Most information shows someone standing at the stove holding a Thermopen in the sugar mixture or some sort of candy mixture. While the old style may not be perfect, at least it can be clipped on the pan. I REALLY do not want to be standing at a pan of scalding hot sugar holding something mere inches away for the entire time watching the temperature rise. Can’t you make the Thermapens with clips?
Martin says
Pamela,
Good question! I understand your point here. It can be uncomfortable holding a Thermapen over high heat for a long time, but you don’t really need to be holding it there the whole time. Spot check it, then get out of the heat! I check more frequently the closer I get to done, and I will often also be lowering the heat as I approach that point so that I don’t risk overshooting.
We don’t make a pot clip for the Thermapen for the exact reason you have already noted: it gets hot over the sides of the pan! While the sensor of the Thermapen has a very high operating range, the internal electronics and the case itself can get ruined by very high heat. If you feel like something that clips to the side of the pan is necessary, I recommend the ChefAlarm, which comes with a pot clip for its probe. It’s the very best second-best option!
Lisa says
Hello, which is the best thermometer for chocolate making? Thank you.
Martin says
The ChefAlarm is best for chocolate making. The high-and plow-temp alarms help keep you in the tempering window, and leaving a probe in your food isn’t a problem for chocolate making like it can be for candy making.
Steve says
Hi, this article is wildly misleading and should be edited. I understand you are trying sell product but lying about it to folks who don’t have a solid cooking background is not cool.
+-2 degrees while working with chocolate is unacceptable. Any apprentice chocolatier who can tie their shoes knows that 2 degrees over the max working temps (90,88,86 – dark, milk, white respectively) can loose the temper. Pastry Chefs who work with chocolate need +-0.2 degrees of accuracy (some of the really good Chefs can deal with 0.5 F).
The REAL old style candy thermometers are mercury (grey liquid) and the absolute most accurate and reliable (but obvious dangers are involved and good luck finding one). The “old style” thermometers you are referring to are most likely alcohol filled (blue liquid) and thus “not as accurate” but are absolutely in the “acceptable range” for sugar work. The exterior design of these types of thermometers is also nearly perfect. Any uneven crystallization during the cooking process has to be handled by periodically “washing” the pot and probe with a brush of water until the boiling slows (total evaporation of water or +212 F) regardless of what type of probe used. ANY foreign object in a pot of sugar will start a seed. The thermopen does not prevent uneven crystallization, careful cooking does. Also, it is CRITICAL when cooking sugar to be able to know how fast the temp is rising (think carryover cooking). Leaving a probe in the pot is the only way to do this.
Also, sugar LOVES to heat evenly. Any uneven temps in the sugar during cooking are due to cheap pots and pans. THICK aluminum pots will help a little with this, quality stainless will almost eliminate this, copper will completely eliminate this. It is not effective or advised to stir sugar to even out temp variation.
I LOVE Thermopens for culinary work (especially Smoking, BBQ and other long term cooks), but to even pretend that they are slightly useable in the pastry world is an absolute joke. Especially when there are $40 digital thermometers out there that do the job just fine.
source – I have a B.S. in Baking and Pastry Arts, 12 years in the field, 5 years of dedicated chocolate work and not one of my thermometers cost more than $50 (save for my thermopen).
Martin says
Steve,
We’re glad to hear that the Thermapen serves you well in your other culinary pursuits but sorry to hear that you find it unsuitable for your pastry work. Some of the top pastry chefs in the country (including both founders of the French Pastry School in Chicago) have told us they find the Thermapen absolutely essential to their pastry work. Thermapen ONE does have an accuracy of ±0.5°F and takes a full reading in less than a second. A Thermapen is also less likely to prevent seed crystals than a leave-in probe because it can be used to spot-check temperatures and then be removed from the chocolate or sugar mixture. That said, it sounds like you have a process that works for you using other tools and we wish you all the best in your work. Let us know if we can interest in you in any of our top-rated leave-in probe thermometers, including the Square DOT that is the first leave-in probe thermometer to provide a running average of your oven temperatures for more precise baking temperature control.
Aisha says
Steve, which thermometer would you recommend for candy making and chocolate making plz? Thank you!
Marc says
I use a ChefAlarm for helping me produce maple syrup. Syrup needs to be re-heated and filtered after it comes off the evaporator. The ChefAlarm is great for monitoring the temperature of the heating syrup. You don’t want to overheat it.
Of course, the ChefAlarm is used all-year-long whenever I roast or BBQ meat. It’s super accurate and durable.
I’ve been a fan of ThermoWorks for years. Best products AND customer service on the market.
Martin says
I didn’t ever think of that application. How cool!
Janice says
Can the thermo dot be clipped to a pan for oil frying? Etc
Martin says
Yes, you can use a pot clip to clip the probe of a DOT to a pot for deep frying, and it’s a great deep-fry thermometer.
Kristin says
I have a Thermopop and while it is more accurate then any candy thermometer I have owned or researched, it is incredibly slow to come to temp. Not as fast as promised! It is not good for spot checking temps because it takes so long to come to temp. It is uncomfortable to use for candy making because my gas stove gets so hot and I also worry about frying the thermometer from prolonged exposure to heat. How accurate is the temp on the chef alarm? I would like something to use for deep frying and making toffee.
Martin says
ChefAlarm is accurate to ±1.8°F and is the best deep-fry thermometer you can get. I use Thermapen ONE for all my candy making, as it is faster than the ThermoPop, but a ChefAlarm can work for that, too.