Degrading of sucrose in a vacuum?

[JMan]

Just a quick question as Im thinking of getting a vacuum pan and cant find the answer anywhere. Does the tempature that sucrose degrades at change with pressure?

 

Just trying to make sucrose grains without them degrading at all.

[MadMat]

Are you talking about carmelization? If so, drawing a vacuum would not change the carmelization temperature of the sucrose at all. A vacuum will only change the boiling point of a liquid. Your idea has merit in that you will be able to boil off all the water without the worry of carmelizing the sucrose. I, personally don't think it is worth the effort though. I have never had any problems with degradation of the sucrose in my Rcandy, at least nothing to the point of changing the performance of the grain.

 

**After thinking about it, there is one advantage to your idea in that it will definitely speed up the cooking process. Under a vacuum, the water will boil off faster.

Edited May 3, 2018 by MadMat

[Simoski]

I agree, pulling a vacuum will lower the boiling point of the water and drive it off quicker.

Similarly it will complicate matters.

[JMan]

I was thinking of pouring the mix in a grain then driving all the water off, this way I could get the water off the top of the grain without burning the bottom.

 

I find normal sucrose cools much too quickly to make any decent sized motor with any consistency.

[Gray]

Vacuum distillation is a great technique and provides for lowered boiling temperatures and better temperature control. There is a subject that should be further examined - using a cold trap / vapor trap in vacuum distillations. There is next to nothing on this subject or affordable labware for this purpose. Anyone got experience using / buying vapor trap to protect pumps from harmful vapors?