Why does my invert sugar always crystallize?
I often use invert sugar as a humectant in confections. The problem is that it always crystallizes after a few days.
My recipe is fairly simple.
- 1 kg refined sugar
- 200 ml filtered water
- 1 g cream of tartar
Bring to boil at 110C. Let cool.
The syrup is definitely inverted, as the taste is distinct. The invert sugar is also completely transparent which tells me there are no obvious undissolved sugar crystals.
Crystallization typically begins slowly at the point where I insert a spoon to portion out the syrup for recipes.
I store the syrup at room temperature in a glass syrup jar. I have had no luck boiling the jar in water to liquify the syrup, as it appears saturated and it returns to the crystallized state. Also I suspect the boiling temperature is above 100C, which the waterbath cannot exceed.
Best Answer
The crystalization is to be expected, that's what inverted sugar does. It is the same thing as with honey, which is chemically nothing but a contaminated inverted sugar. So, you are not doing anything wrong. In an inverted sugar at sucrose ratios, you will get sucrose crystalizing back out of the solution, just as you are observing now.
If you really need it smooth, you can try changing the ratio by adding some fructose, as such a mixture is less prone to crystalizing.
The one thing that puzzles me in your description is that you cannot get it back smooth by heating, this should in principle be possible. Maybe try adding a bit of water to the syrup itself during heating, so it can dissolve again.
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Quick Answer about "Why does my invert sugar always crystallize?"
Supersaturation is an unstable state. The reason the solution is unstable is it contains more solute (in this case, sugar) than can stay in solution—so as the temperature decreases, the sugar comes out of solution, forming crystals. The lower the temperature, the more molecules join the sugar crystals.Does invert sugar crystallize?
It is sweeter than table sugar, and foods that contain invert sugar retain moisture better and crystallize less easily than do those that use table sugar instead. Bakers, who call it invert syrup, may use it more than other sweeteners.How do you stop sugar from crystallizing?
Adding a little corn syrup or an acid such as citrus juice will help to prevent this. Selecting a syrup recipe that includes a little brown sugar gives pancake syrup a warm color and the acid in brown sugar helps to prevent crystallization.Why does my sugar keep crystallizing?
Why is my sugar crystallizing? Unclean pots and pans, hard water, excessive stirring, and impure sugar can all cause sugar to crystallize. Sugar will latch onto particulates like minerals in the water or even foreign objects like your stirring spoon.Why does invert sugar prevent crystallization?
Compared to sucrose, inverted sugar is sweeter and its products (glucose and fructose) tend to retain moisture and are less prone to crystallization.What is Invert Sugar and Why Should I Care?
More answers regarding why does my invert sugar always crystallize?
Answer 2
My first guess would be your pan was dirty or not completely clean, happens quite a lot when boiling sugar that spits from the boiling cristalize on the side and "infect" the other sugar. Did you wash down sugar on the sites while it was boiling to reach the desired temperature?
Answer 3
From what you describe, I seems to me that sucrose in your syrup is just poorly hydrolyzed. In other words, the syrup still has a lot of sucrose so sucrose crystals form when possible:
- when disturbed with a spoon
- when heated up
The taste will be distinct anyway because of cream of tartar, so I doubt it's a robust criterion of invert syrup.
Possible causes:
- boiling time. Time is crucial for sucrose hydrolysis and you haven't specify how fast do you boil it up to 110 C. From a huge sucrose/water ratio my guess is - not too much. I would suggest 20-30 min boiling time. You would need less heat, more water and more of CoT for that.
- the quantity of cream of tartar. I know that 1g per 1kg sugar is a common recipe found on the internet, but it doesn't make any sense to me. Cream of tartar (and all possible acid substitutes) is not a reagent here but a catalyst and what matters is pH, thus, CoT's ratio to water. This is to keep in mind if you would consider increasing amount of water for longer boiling. As for you case the amount of cream of tartar is enough, though you may consider rising it up to 2g.
- possible undissolved crystals. You said, you don't see any and that's a good sign. But there still might be really tiny ones. I would actually suspect them to be there because that amount of sugar only dissolves completely in that amount of water at 100 C and it seems it doesn't have much time to finish dissolving till 110 C when you start cooling.
Answer 4
Also, you may have luck using a microwave for re-liquification. Myself, I have always ended up scorching honey when I have tried, but many swear by it, and if you can do it with honey, you should also be able to do it with invert sugar solution.
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