Balancing technological sugars in ganaches

Sucrose molecule © Karl Harrison 3DChem.com
Having a basic understanding of sugars and how they interact in ganaches is an important piece of knowledge every chocolatier should delve into. Chocolatiers often overestimate the shelf life of their bonbons. In hotels and restaurants, this post is probably a little bit less important, but even in that case, I would urge you to keep reading as some of the properties of the different sugars I’m covering here will also apply to pastry preparations and can improve their quality, taste and shelf life. We often talk about ‘sugars’ in ganaches. The late Jean Pierre Wybauw recommends a minimum ‘sugar’ content of 25% while Ramon Morato goes even further and recommends a minimum of 30% to achieve a balanced recipe with optimal texture and shelf life. It’s important to note that we talk here about ‘sugars’ as a group and not sucrose, commonly known as ‘caster sugar’ or ‘granulated sugar’ which is more specifically a disaccharide consisting of glucose and fructose molecules. To avoid confusion, I will only refer to this sugar as sucrose in this article. Sucrose is probably one of the worst sugars to use in ganache, to understand this we need to look at the state of sugar at room temperature: it’s a coarse crystal. Because of this Sucrose will, over time, re-crystallise and release water in the recipe leaving you with a reduced shelf life and subpar texture.
Why you need to include sugars in your ganache
A ganache is an emulsion; meaning it’s a mixture of water and fat. As water is what most microorganisms need to thrive, we need to “bind” this water to make it unavailable for those microorganisms to multiply. The value of “bound” versus “unbound” water is reflected by the so-called ‘Water Activity’ or simply put ‘AW.’ A higher value equates to a higher amount of unbound water, which means the circumstances are more beneficial for microbial growth. A water activity measurement of 1 means there is 100% of free water, a measure of 0.5 means there is 50% of free water.
Water activity measurement |
Shelf life |
>0.85 |
Shelf life of the ganache is less than 2 weeks |
0.85 – 0.70 |
Shelf life of the ganache is between 2 weeks and 6 weeks |
0.70 – 0.65 |
Shelf life of the ganache is between 6 weeks and 3 months |
<0.65 |
Ganache is stable and shelf life exceeds 6 months |
When we look at a ganache that is made up of just cream and chocolate, the score is usually well over 0.90. If you want to be able to plan your production and not produce your entire collection every other day, you will have to find a way to reduce the water activity. Sugars are your primary tool to achieve this. Adding certain acids also help to lower the chances of microbial growth, but this will not be suitable for every flavour profile. I’m also not a fan of resorting to alcohol as you will effectively cut out one-fifth of the global population as potential buyers of your product.
Which sugars are suitable
So if we can’t use good old sucrose in our ganaches, which ‘sugars’ can we use? Typically a combination of different sugars will do the job, to make a decision we there are a few things we need to know.
Sweetening power
If we consider our ganache will contain anywhere between 25 to 35% of sugars. The sweetening power of the sugars we will use will be of critical consideration; after all, we don’t want overly sweet chocolates. To understand this, we consider sucrose the benchmark, which has a sweetening power of ‘100’. In the below table I’m limiting myself to sugars we will typically use in chocolate, ice cream or pastry.
Sugar | Sweetening power | Structure |
Sucrose | 100 | Disaccharide |
Dextrose | 70 | Monosaccharide |
Glucose syrup | 74 | Monosaccharide |
Sorbitol | 50 | Sugar alcohol |
Glycerol | 60 | Sugar alcohol |
Maltitol | 90 | Sugar alcohol |
Invert sugar | 120 | Combination of fructose and glucose. |
If we look at the above relative sweetening powers of the different sugars, and we keep in mind we need to reach a total of 30% of ‘sugars’ (including the sucrose which is already present in the couverture we will be using) we want to avoid using too many sugars which have a high relative sweetness. Especially when we need to achieve a longer shelf life and need to increase the sugar content even more, this becomes important. Relying solely on invert sugar for example will result in a product that is too sweet, combining with a combination of sorbitol, glucose and or glycerol is the better way to go for creating the optimal balance between shelf life, balanced sweetness and optimal texture. Below I will break down several different sugars that I often use in my chocolates.
Glucose
Glucose molecule
Benefits of glucose in chocolate are:
- Binds water thus reduces free water content. (lowers water activity)
- Prevents re-crystallisation of sucrose in the recipe.
- Makes a more elastic ganache.
- Slows down the drying of the ganache.
Because glucose prevents re-crystallisation of sucrose, I recommend to always add a small amount in your recipes for this reason alone. Glucose syrup contains water, and so that will need to be accounted for in the total water content of the recipe. The amount of water is referred to in ‘Beaumé’, and typically glucose syrups come in the following forms: 43 BE = 80% dry substance 45 BE = 85% dry substance For ganaches, it’s advised to opt for 45BE as you will end up adding less water to the recipe. Another point to keep in mind is the ‘Dextrose Equivalent’ abbreviated to DE. Dextrose is the product of hydrolysis of starch. The further the hydrolysis process proceeds, the more reducing sugars are produced, and the higher the DE. Typically we find glucose syrups varying from 42 DE to 63 DE in industrial settings. The lower the DE, the higher the amount of dextrin and the lower the amount of reducing sugars. Higher DE glucose syrups have low amounts of dextrin and high quantities of reducing sugars. Note:
- Dextrins are low-molecular-weight carbohydrates produced by the hydrolysis of starch or glycogen.
- Examples of reducing sugars are: glucose, fructose, lactose and maltose or simply put monosaccharides.
- Glucose syrups with a higher DE and thus a high amount of reducing sugars are sweeter.
For shelf life optimisation it is recommended to use 45DE glucose syrup, it contains a good amount of reducing sugars which are more effective at binding water and preventing drying out of the ganache. A lower DE glucose syrup will make the syrup more viscose. Note: while glucose certainly has a place in a ganache it is relatively ineffective compared to other sugars in reducing water activity, to have a long shelf life glucose syrup should only be one element in the arsenal of water activity lowering ingredients in the ganache.
Invert sugar (commonly known as Trimoline)
Fructose & Glucose molecule
Invert sugar is sucrose inverted by the enzyme ‘invertase’ and so becomes a mix of glucose and fructose (approximately a 50/50 ratio). Invert sugar is particularly hygroscopic (water-attracting) and therefor an excellent addition to any ganache to make sure the ganache doesn’t dry out. In doing this, the water activity will also drop significantly. Honey is almost identical to invert sugar, and they can be substituted with each other. A few notes of caution:
- Excessive use of invert sugar will make the ganache sticky and soft, which could be a significant issue for chocolates that will be enrobed.
- It’s advisable not to heat invert sugar over 70 degrees C as fructose will start to degrade at this point, resulting in a loss of water activity lowering properties.
- Invert sugar is quite sweet (sweetening power of 125%), so go easy on it.
Sorbitol
Sorbitol molecule
Sorbitol has a bad rep. For being an ‘E-number’. Let me set the record straight though; sorbitol is a naturally occurring ‘sugar alcohol’ and can be found in grapes, pears and many other fruits! It is true that in excessive amounts, sorbitol can have laxative effects, it would take some severe chocolate-eating however, to get anywhere near the necessary dose for that. Sorbitol has quite strong water activity lowering properties while only boasting 50% of the sweetness sucrose has, because of this it can be used in relatively larger quantities compared to invert sugar without the end product becoming overly sweet. The recommended dose of Sorbitol is 5 – 10% calculated on your recipe.
Glycerol

glycerol molecule
Another one with a bad rep. For similar reasons to sorbitol. Like sorbitol, glycerol is a naturally occurring sugar alcohol. Some chefs claim that they don’t like the texture, but I would challenge anyone to taste several chocolates blindfolded and point out which ones have glycerol in them… I’ll be impressed if anyone can guess them all correctly. (if the ganaches were balanced correctly of course.) Glycerol has the most potent water activity lowering properties of any sugar we have discussed in this article, if a long shelf life is a must (think beyond four months without freezing) I find it challenging to achieve this without the inclusion of glycerol. Key points of glycerol:
- Glycerol is approx. 2 times stronger than sorbitol at binding water or lowering water activity.
- The dose is 3 – 5 %, exceeding 12% will result in a bitter unpleasant after taste.
- Glycerol has a sweetening power of 60, so quite a bit lower than sucrose.
- Glycerol is a sugar that is naturally occurring in our bodies amongst other places.
Applying this in our recipes to get an optimal shelf life
Ramon Morato recommends that for optimal shelf life, a ganache should be roughly made up like this: Max. water content: 20% sugars content +/- 30% Cocoa butter +/- 21% Dairy fat +/- 15% A real-life example of such ganache would be:
Cream 340g Invert sugar 90g Glucose 40g Sorbitol 100g 65% chocolate 620g Anhydrous butter 140g
Or broken down more:
Weight |
% |
|
Total |
1,330g |
100% |
Sugar content |
441g |
33% |
Fat content Of which cocoa butter Of which milk fat |
507g 248g 259g |
38% 18% 20% |
Water content |
228g |
17% |
Other dry substance |
155g |
12% |
To get to this calculation, we need keep in mind: Cream (UHT) contains 35% dairy fat and 65% water 65% couverture contains 35% sucrose and 40% cocoa butter Glucose syrup contains 85% dry substance and 15% water.
Contrary to what you would probably expect, this ganache made under normal circumstances would have a water activity reading of about 0.78, so in optimal conditions only a shelf life of about 6 weeks. As you can see if you want to exceed 8 weeks we will need to consider the inclusion of glycerol.
Note: When shelf life is not essential, we can increase the water content to our liking (within reason), In commercial chocolate shop settings however it is vital to follow the guidelines outlined in this article. People tend to overestimate significantly their shelf life, which could ultimately lead to expensive lawsuits, don’t let it get to that! 😉 Update 02/07/2019: Since last writing this blog post, I took a masterclass with Alexandre Bourdeaux, one of the leading Barry Callebaut chefs and technical advisors, on shelf life. During those days, I learned that he broadly agrees with the ratios outlined in this post but to make things easier for us chefs to calculate our recipes faster he created a software called Ganache solution, I was sceptical on its use but after being shown how easy it is and how much time it can save I invested in this software, I would highly recommend professional chocolatiers to use this software. Note: The properties of these sugars extend beyond the world of chocolate bonbons. Including a % of invert sugar in baked goods, for example, will keep the product moist longer and thus increase shelf life. If you would like to learn more about this topic, two books have helped me a lot in understanding this topic better: One is the collection ‘Fine chocolates’ by J.P. Wybauw or the book ‘Chocolate’ by Ramon Morato.
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Hi, I have been reading Ramon Morato’s book and I can’t find anything about substituting ingredients. If you don’t have sorbitol on hand but only have invert sugar and glucose. Would it be possible to substitute this and to what proportion? Thank you.
Sorbitol is not mandatory, what is mandatory is correct balance of sugars, taking into account the relative sweetness of the different sugars and their technical properties.
The big advantage of sorbitol is that it increases shelf life quite a bit without adding too much sweetness.
You can absolutely create a good recipe though with only invert sugar, glucose, and/or potentially caramelized sugar (as it is caramelised it becomes a lot more hygroscopic compared to plain sugar and will not re-crystallise). Dextrose if you can find it is also a great addition if you can’t source sorbitol as it is also less sweet compared to invert sugar and quite potent at increasing shelf life.
Just remember, that if you are not including sorbitol in your sugars mix, the shelf life will be a lot shorter compared to a recipe that does have sorbitol.
Thank you for this post! Even though I’m not a chocolatier, I find all the information very interesting. I’m a fondant cake artist and I use ganache to cover my cakes before applying the fondant. When you talk about the shelf life of the ganache in the AW list, what temperature are you referring to? Are we talking about room temperature or the fridge? How long does a ganache keep fresh in the fridge and frozen (I freeze my leftover ganache to use it later on). How does that change when I add alcohol?
Thank you!
Hi Iris,
With a ganache when we talk about shelf life we mean at room temperature, of course that means well encapsulated by chocolate as that seals it off from any moisture and contaminants. We also assume it is stored in a dry dark place when we mention these shelf lives.
A ganache can easily be kept for a year in the freezer, in the fridge it depends again on the balance of the formulation, if we are talking about just cream/butter/chocolate it will be less than a week, a recipe like the one discussed here would probably be 6 months. But even so, it’s wise to have your recipes tested in the lab for shelf life before making any claims on the label 🙂
Regarding alcohol, a ganache is considered shelf stable at around 4% alcohol content. (So at least 6 months room temperature)
A few caveats though, shelf life is strictly measured by microbial growth, a recipe can be shelf stable, but over time the taste and texture will inevitably degrade.
My recipes are all tested and came out 6 months shelf life, but after 3 months there is a noticeable decline in quality, so I limit my shelf life to 3 months.
Hope that answers your questions!
Hi, I really appreciate this article. I currently make my bon bons with trimmoline. The AW is still pretty high, averaging .85-.97. I’m trying to get the ganache down to .65-.70 for a longer shelf stability. Do you think replacing the trimmoline with glycerol would help with getting that number down?
Hi Alea, relying on one source of sugars is usually less than optimal.
Glycerine will certainly help, but I believe a good recipe has a mix of Glucose (I always have glucose in my recipes for its anti-crystallisation properties), invert sugar (trimoline), Dextrose if you have any fruit present, sorbitol, and then only if that didn’t do the trick, I would look at including Glycerin
Hello i really like your article.I would like to ask can I replace sorbitol or dextrose with xylitol and erythritol?
Hi Marta,
Xylitol and erythritol are both more typically used as sugar replacements. To be honest I’m not sure how they behave in terms of shelf life and the lowering of water activity. If you have access to a water activity meter, you could make 1 recipe with sorbitol, and one with xylitol, do a test and see how they compare. That would be quite an interesting experiment!
Hi dear chef Erik , i would like to thank you for the article , I learned a lot of new techniques
my question is about how can the flavour be saved and has a long time stability with the same quality of the first day’s taste especially the pistachio and hazelnut paste
Note:- for the ganache I use flavour paste with cream, chocolate and chopped hazelnut or pistachio?
Hi Erik,
Thank you so so much for this simply amazing post about these sugars! I have just landed my first job in a chocolate shop, and although my passion and enthusiasm for chocolate making is 100%, I haven’t come from a pastry background, so have no training or knowledge about these important elements and ingredients! I have been taking notes from the Chocolatier at work and doing my homework to try and improve my knowledge about these elements and your blog posts have been so helpful. I think I have spent most of today looking at various sugars and your post is by far the more detailed and helpful!
I now know a bit more about why each of these sugars are used and why balancing them is important to not over-sweeten your ganache, I wonder is there any best way to chose which sugars to combine? Are some better together than others, is a bit of everything best, or just one or two with a balanced sweetness, or is experimentation key in working out which works best in your ganache?
Thank you again so much for your help and sharing your expertise.