7

I recently decided to make something that required liquid glucose, 140g of it. No problem in general, but for some reason none of my usual suppliers had stock (even tried pharmacies). The closest I found was glucose powder.

Unfortunately, having no clue how to "re-hydrate" the powder to a liquid form, I experimented. :-)

I can safely say that 100g glucose powder was way to much as a substitute for 140g of liquid glucose (which I expected).

However, I was wondering if any of you had a convenient method of turning powdered glucose into the wonderfully thick and sticky liquid glucose, in case I ever find myself in that position.

Improve this question
1
  • 4
    Chemically speaking, saying "liquid glucose" is inaccurate. To explain, at normal temperatures, glucose is a solid; depending on the isomer/chiral form, melts at ~150°C, and is a liquid above that temperature when not under pressure. ...What you want is a solution (syrup) with water. Glucose also dissolves in nonpolar solvents for other 'liquid' solutions.
    – zanlok
    Commented Nov 30, 2012 at 18:50

5 Answers 5

Reset to default
8

Well, the answer is "it depends." This is pretty much the same as asking, "I have sugar, and I want sugar syrup. How much water do I add?" It depends on the concentration you're looking for. If you're looking for a 24% solution, it's 24 grams of glucose in 76 grams of water. A 30% solution is 30 grams of glucose in 70 grams of water, etc, etc.

Unless you have some chemical reason to avoid dextrin, you can just substitute corn syrup. The only reason they use glucose in Europe is because they don't have our superabundance of corn.

Improve this answer
3
  • 2
    I live in South Africa, and unfortunately corn syrup is not generally available. We base most of our syrups and sugars off sugar cane.
    – brianb
    Commented Aug 25, 2011 at 17:11
  • 2
    Sorry, forgot to ask. What is considered a standard concentration when recipes say "140g liquid glucose"? I assume from your examples it would be between 20% and 30%, or am I drawing too many premature conclusions? )
    – brianb
    Commented Aug 25, 2011 at 17:14
  • 1
    @brianb: Yea, in Europe, I think it's mostly derived from grapes? You could try using honey, though honey has more water. If I were trying to re-create it, I'd keep adding powder until the mixture was a thick syrup, and go with that.
    – Satanicpuppy
    Commented Aug 25, 2011 at 19:28
10

I had the same problem yesterday and asked a chemist friend and he told me that the solubility ratio of glucose powder to water to make liquid glucose is 91gm powder to 100ml water. I mixed the powder into the water and zapped it in the mw for about 2 mins and it was fine. Recipe worked a dream!

Improve this answer
1
  • I tried lower and higher concentrations and both failed for me. I ran out of powdered glucose and managed to find liquid again, so haven't needed to experiment anymore. However, I will definitely try again with that ratio just in case I ever find myself stuck again. Thanks :)
    – brianb
    Commented Dec 15, 2011 at 18:28
2

Glucose syrups contain 70-91% w/v solids, with at least 20% dextrose. If you're mixing glucose powder and water only, use 70g-91g glucose for every 30g (30mL) water, and heat the mixture in a double boiler (or carefully in a saucepan) until all sugar is completely dissolved.

It will be thick!

Take care not to heat the solution for too long or you will lose too much water to evaporation. If you know the weight of your top pot/saucepan you can weigh the glucose mixture in it while working to check how much water remains and whether you should consider replacing lost water.

Be sure to dry the bottom of your top pot before weighing if you do this, and be careful moving about pans containing hot liquids.

Keep in mind that any additives or alternative sugars count towards the solids weight fraction and may require more or less water to dissolve than glucose alone.

It's much easier to make a 75% glucose syrup than a 90% glucose syrup as you are less likely to have problems with poor supersaturation (dissolving of sugar) or re-crystallization during cooling if you use a lower concentration. It will work just fine in your recipe, either way.

Improve this answer
-1

I've a got a simple recipe for all of you. Just take 2 cups of sugar, 1/4 cup of water, 1/2 tsp. lemon juice, pinch of salt, 1/2 tsp. of baking soda. Add all of the ingredients to a sauce pan, cook for about 5 minutes and your glucose syrup is ready to use.

Improve this answer
3
  • 1
    I assumed you were referring to baking soda. Your cooking instructions could use a little more depth. Cook at what temperature? Do they stir the ingredients once they are added to the sauce pan?
    – Chef_Code
    Commented Apr 24, 2015 at 23:01
  • Why add both some amount of acid and base?
    – Nick T
    Commented Feb 17, 2021 at 16:10
  • @NickT likely for fun
    – Alchimista
    Commented May 7, 2021 at 11:12
-2

I tried making my own glucose syrup, as there were no speciality baking shops in my vicinity.

I did it mixing:

  • 35 g (2.5 tbsp) of water with
  • 2 tsp fine sugar
  • 1 tsp cornflour

You can adjust the amount of water used, by using a little more or a little less of it.

Improve this answer
1
  • 1
    This is not glucose syrup, it is sugar syrup. It won't act as glucose syrup, specifically it won't prevent crystallization in candy making.
    – rumtscho ♦
    Commented Nov 29, 2012 at 21:13

Not the answer you're looking for? Browse other questions tagged or ask your own question.