DIY Belgian Candy Syrup 2: Experiments

[Miniseries part one, two]

In part one, I went in to some of the science behind making syrup from sugar.  Here, I’ll go into some of the experiments I tried before coming up with something I felt worthy of risking five gallons of brew over.

The general procedure is to heat sugar, water, and a source of amino acids.  As the water evaporates, the sugar solution’s boiling point will rise.  While heating, keep in mind that as the temperature rises and water evaporates, there is less thermal mass in the pan, so the temperature will rise more quickly (ie if it took 10 minutes to go from 240-250F/ 115.5-121C, it might only take a minute or two to go from 280-290F/ 138-143C).  The ending boiling temperature, and thus the ending water content, will determine the state of the sugar when it is cooled; 240F will result in a syrup.  Simply heat to the desired temperature for chemical reactions, cool with the addition of water below 240F/ 115.5C, then bring back to 240F/ 115.5C before cooling.  Be extremely careful when adding water- the solution is well above the boiling point of pure water and can instantly vaporize and spit the sticky hot syrup well out of the pan.  To store the syrup, I like to use some small mason jars; you’ll need to cool the syrup first or the glass will shatter from thermal shock (or I suppose you could heat the glass to the temperature of the syrup if you wanted to be difficult).

Belgian candi syrup

Home made Belgian candi syrup

My first attempt was a bit of a stab in the dark.  I used enough tap water to dissolve 1 lb/ 0.45 kg of sugar and 3 tbsp/ 44.3 mL of DAP (diammonium phosphate).  The DAP is meant to provide a source of amino acids, necessary for the Maillard reactions as covered in part one; you’ll notice an ammonia smell as the DAP decomposes when it heats.  I quickly found out that my Walmart meat thermometer was useless at the required temperatures, and was essentially running blind.  You’ll want a very accurate thermometer that can read into the hundreds of degrees (a good candy or laboratory thermomter), as a few degrees will change the end product consistency drastically.  The result was a black, acrid burnt syrup which mellowed after a few weeks, but not enough to be usable.

I attributed the acrid flavor to fructose which scorches at a lower temperature than other sugars.  I decided to add pickling lime to make the solution more basic, because sucrose will invert into glucose and fructose faster in a more acidic environment.  Additionally, the solution will acidify as it caramelizes and undergoes Maillard reactions.  But, as I research it further now, DAP is known to decrease the charring temperature, so this might explain a lot of things too.  Perhaps the DAP is lowering the scorch temperature of the sugars and causing them to burn.  I don’t know enough about the specific chemistry taking place with the DAP to offer more than a guess.

In the next batch I added molasses and used Wyeast yeast nutrient in addition to the DAP to increase the complexity of the amino acids present for reaction.  I also started using distilled water to cut down on experimental variables; distilled water is of a predictable pH and has no other dissolved solids.  Just keep in mind that once distilled water is exposed to the atmosphere, it will slowly drop a bit below a pH of 7 by dissolving CO2 into solution, forming carbonic acid (the same stuff that gives your tongue the prickly sensation when drinking anything carbonated).  I only went to 268F/ 131C with this batch, but only because the temperature started falling.  As it turns out, the sugar had crystallized on the bottom of the pan, forming an insulating layer.  Lesson learned: stir the sugar more or less constantly (if there are any candy makers in the audience, they might disagree- the stirring can cause course sugar crystals to form in some instances by forming seed crystals, but this is not really a concern once the sucrose begins to invert).  This batch (1 lb/ 0.45 kg sugar, 1/2 tsp/ 2.5 mL lime, 1 tsp/ 4.9 mL nutrient, 1 tsp/ 4.9 mL molasses) turned out light brown and melt-in-your-mouth buttery, and completely solidified as it cooled- not the most fun to clean up.

I used the same general process and took it to 300F/ 149C (1 lb/ 0.45 kg sugar, 1/2 tsp/ 2.5 mL lime, 1/2 tsp/ 2.5 mL nutrient, 1/2 tsp/ 2.5 mL DAP, 1 tsp/ 4.9 mL molasses) and got a syrup with molasses-like flavors and raisins, with some burnt sugar up front.  This was a syrup I felt good enough to brew with, but I wanted to push it further.  I also noticed some grainy clumps in the syrup, which I think was the lime or more likely something in the nutrient not dissolving, but I was never able to be sure.  This didn’t concern me for brewing, as I knew it would just be dissolved or fall out of solution at some point.

I next tried multiple heating cycles, reasoning that I could induce more flavor without increasing the temperature and charring.  For this batch (1 lb/ 0.45 kg sugar, 1/2 tsp/ 2.5 mL lime, 1/2 tsp/ 2.5 mL nutrient, 1 tsp/ 4.9 mL DAP, 1 tsp/ 4.9 mL molasses), I used 3 heating cycles, each to 290F/ 143.5C, cooling to below 240F/ 115.5C each time with the addition of water.  Unfortunately burnt and tart flavors overpowered a delightfully fruity background.  During cooking, there was a divine cherry-rum aroma which I was never able to reproduce in the flavor.  Another odd thing I noticed was that upon each reheating, there was less of a tendency for the sugar to crystallize.  I attribute this to the further inversion of the sugar.  Glucose and fructose will disrupt the crystalline structure of sucrose, slowing crystallization.

My next batch (1 lb/ 0.45 kg sugar, 1 tsp/ 4.9 mL lime, 1/2 tsp/ 2.5 mL nutrient, 1 tsp/ 4.9 mL DAP, 1 tsp/ 4.9 mL molasses), I heated to 280F/ 138C four times.  The result was a flavorful but slightly tart syrup (indicating acid), with no burnt flavor, but otherwise completely uninteresting.

By this point, I got tired of trying to avoid charring.  As I was attributing it to the fructose from the inverting sucrose, I decided to use some glucose sugar I had for priming bottles.  I immediately noticed a change in consistency and a lack of crystallization, as well as how much more rapidly the syrup darkened (even before 240F/ 115.5C), presumably a result of how much more reactive this simpler sugar is.  For this batch (1 lb/ 0.45 kg glucose, 1 tsp/ 4.9 mL lime, 1/2 tsp/ 2.5 mL nutrient, 1 tsp/ 4.9 mL DAP, 1 tsp/ 4.9 mL molasses), I heated to 290F/ 143C, then to 270F/ 132C four more times.  Oddly, this batch also had a burnt flavor, even though it was never heated anywhere near the decomposition point of glucose.  I suspected it was some product of the reactions, but I now think it may have been the DAP causing scorching.

I went back to basics with my next batch (1 lb/ 0.45 kg sucrose, 1 tsp/ 4.9 mL lime, and 1.5 tsp/ 2.5 mL DAP).  I also went with a relatively low temperature cycling between 240F/ 115.5C and 260F/ 126.5C fifteen times.  This batch I would call a success, with a definite raisin and plum flavor with no burnt character, though it seems as if it could go through additional cycles.

My final batch (2 lb/ 0.91 kg sucrose, 1.25 tsp/ 6.2 mL lime, 3 tsp/ 14.8 mL DAP) was based off of the previous batch, and was meant to be what I used in my beer, hence the scaling up.  I had read that lime should not be scaled up directly with the rest of the recipe to avoid a mineral off flavor, but given the tart burnt flavor, I suspect I needed more.

Since this batch didn’t turn out, I used two previous batches in my beer (the third and seventh).  It turned out quite well, with a flavor profile very close to Chimay thanks to the White Labs WLP575 yeast blend, though it was quite a bit more thin due to the low mash temperature of 140F/ 60C.  My one complaint is a slight dry acridness on the back of the tongue about 30 seconds after swallowing which I think is from the syrup.  But, that’s being very persnickety- no one else has noticed this off flavor.

This work was based on some great experiments done over at Ryan Brews and Nate O.’s Brew Log.  And another source, from another engineer.  [2013.11.21 UPDATE: Another great recent experiment over at Sui Generis: Part One and Two.  He beat me to trying DME as the sugar source and it seems to have produced good results.] [2014.11.14 UPDATE: Found another source of info from back in 2009 on the homebrewtalk forums.]

[Miniseries part one, two]

– Dennis,
Life, Fermented


About Dennis
Home brewer, home chef, garage tinkerer. Author of Life Fermented blog.

9 Responses to DIY Belgian Candy Syrup 2: Experiments

  1. ryan says:

    Your last tidbit about maillard reactions with all sugars isnt correct. Nate had it right, the only type of sugar that can undergo maillard reactions are reducing sugars.

    By this I mean an open chain sugar that contains an aldehyde or ketone group. Common reducing sugars are glucose, fructose, galactose, lactose, etc. While sucrose is definitely not a reducing sugar because the bond between the monomers (fructose, glucose) that form sucrose occurs on the reducing ends of each

    Your burnt flavors your getting at lower temps is still likely to be dehydration reactions that are causing the sugars to carbonize. At depressed pH dehydration reactions will occur at temps lower than you think, also during this time maillard/caramelization reactions stop. In the beginning the pH is probably fine, but as maillard/caramelization/inversion happens it creates acid and the pH starts to drop. Which is sort of made worse by using lime, as lime will increase the pH but it destroys the alkalinity of the solution (buffering capacity) supplemental additions of lime (mixed in water) will help to stop this.

    One thing Ive also learned just recently from some lab testing I did, it that I believe we are not using anywhere near enough aminos in any recipe for candy sugar that Ive seen. But I have to go back and test the nitrogen levels in some of the yeast nutrients to see just how much we need to add to get to the level of real D2 syrup.

    Good luck with everything and Im glad your beer turned out well!

    • Dennis says:

      Hmm. What you’re saying does make sense, but it still doesn’t quite jive with how I am interpreting a few sources I have looked at. I’ll go back sometime soon and see if I can’t properly hash this all out and update my post.

      Your comment on aminos makes me wonder whether DME, especially wheat DME, could be used in place of sucrose for this. It would have many of the wheat or barley proteins still available. At first glance it appears as though maltose can invert similarly to glucose, but maybe a 50/50 mix of pure glucose and DME would work better. UPDATE: Maltose is actually a reducing sugar thanks to a free aldehyde, so it looks like the glucose would be completely unnecessary.

      Thanks for your help.

    • Dennis says:

      Well I looked it up when I got home and McGee says in regards to Maillard reactions “the sequence begins with the reaction of a carbohydrate molecule (a free sugar or one bound up in starch; glucose and fructose are more reactive than table sugar) and an amino acid (free or part of a protein chain).” I have been able to verify protein chains being able to participate in other sources, but all other sources specify requiring a reducing sugar.

      I have updated both posts accordingly.

  2. Dennis says:

    2013.08.27 UPDATE: Whew, I think I got all of the measurements into metric in this post.

  3. Alex Duwell says:

    I put DME or Table Sugar with water in a 1:10 ratio in a pressure cooker with some cream of tartar and cook it for 20min. This holds it at 125 degrees without any chance of burning or needing to watch it. I then let it cool and add it to the beer a day into fermentation (the pressure cooker sterilizes the mix so it’s ok). The process turns the mixture into a dark amber colour and it smells fantastic. I add it after fermentation as I don’t want the yeast eating the simple sugars before the maltose is gone.

    Give it a try. Maybe it’s just silliness. But it’s something i stumbled upon when making a yeast starter.

    I’ve also thought about adding some hops to the process to see if you can get better utilisation from the hops at the high temperatures. But I havn’t had the guys to do it yet.

    • Dennis says:

      It just took my brain a second to realize you were in Celsius- I thought for a moment something was very wrong with your pressure cooker (125F = 52C). Making candy syrup this way is actually ideal, I just don’t have one at my house. Normally to get a a temperature high enough for the Maillard reactions to occur, the solution has to be above the boiling point of water- in other words dry or have a very high sugar concentration. Thus the high risk of burning and scorching. But a pressure cooker gets you around this limitation, allowing these reactions to take place in a wet environment, without as much fear of blackening. It also makes for some delicious carrots, onions, or any other veggie with a high natural sugar content (colloquially called caramelized carrots or onions, but they should really be called Maillard carrots).

      I’m not sure how the hops would react to this treatment. You might end up with an over saturated solution, and the extra oils would pretty quickly drop out of solution- there is only so much hop oil you can force into a wort/ beer solution. Worst case the oils would coat your yeast more than normal and slow fermentation, but that would probably take a lot of hops before you had to worry. At the very least, you would almost certainly get to the maximum concentration much faster (say, in 30 instead of 90 minutes), and probably a different balance of hop oils. A similar thing happens if you do a tincture of hops or spices by soaking in alcohol. By pressurizing and forcing the oils into the alcohol solution, it takes less time and you get a different balance of oils as compared with letting it sit longer at standard pressure. You might find this different balance pleasing or not, perhaps depending on the variety. In the end, the goal isn’t the greatest utilization of hops of grain, its the best beer, so let your senses guide you.

  4. Brian says:

    Hi Dennis! Great work here. Reminds me of what I went thru in 2004. Finally I went to Belgium and learned all there is to know(mostly) about Candi Sugar. Anyway, I think I can add a few things. 1- Candi Sugar starts with refined white sugar. Cane or Beet is used depending on current prices. 2- Sugar and water are heated with HCL to invert. Then a base is added and continued heating. Then the secret amino is added. When the solution is at the desired flavor and color it is poured into large metal containers and metal plates are lowered into the syrup. During cooling, rock sugar is formed on the plates. After the rock sugar plates are removed, the leftover syrup is mixed with invert syrup and sold as candi syrup. 3- The total percentage of caramelized syrup present in the candi syrup is aprox 4%. This accounts for high fermentability of the candi syrup and nice pleasing flavor. The base syrup is not so. I can tell you that only 2 companies produce candi syrup and only one is producing high quality syrup and that company supplies all the Trappist breweries. The labs at these productions are amazing! I have noticed that there are now at least two US companies that are producing candi syrup. I would be very concerned with small producers making this stuff. During your research, I am sure you have seen all the horrible things that are produced when burning sugar. I am not sure why the home-brew suppliers are not concerned with any sort of product documentation but I wouldn’t trust an unlicensed food production. I can tell you that the large breweries care very much. Sorry for the long post. I hope that I have added something of value to this discussion. Brian

    • Dennis says:

      Hi Brian,
      Thanks for the additional info! I think the most valuable lesson I learned in all of my research and experimentation is to pay the $5 or $6 per lb for D-180. I’m glad I looked up all the science and tried it, but I think there are other areas I could focus my effort on in the future to make a great beer. Perhaps some day I’ll get make to making the syrup, but for now I’ll leave it in the proof of concept phase…
      – Dennis

  5. Brian says:

    I totally agree with you on the money and the effort. But i’d ask for the documentation on that d-180. Im not in the business anymore, but I still believe in clean process and documentation. If you are ever in L.A. stop by the brewery for a beer. Cheers!

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