Ask the Alchemist #171

Level: Apprentice

Reading time: 4 min

I understand the no liquids rule, but I was wondering whether glycerin could work as sweetener? If it’s present in all natural fats, it shouldn’t be too much of a problem, no? I’m interested in its low glycemic index, and it seems ideal on paper. Is it possible or am I really off the mark?

When we talk about cocoa butter and tempering, you may often see the abbreviation TAG.  This stands for Tri-Acyl-Glyceride.  To translate that, Tri is three, acyl is a long chain hydrocarbon (the oil or fat) and the three Acyls are connected on a glyceride backbone.  So, yes, glycerin is present in some form or another.  But it usually is not in its free state.  It likes to attach to thing, hence the TAG.

On its own it still likes to attach to things and therein is the first issue.  By itself glycerin attracts water like a sponge.  Glycerin is often added to lotions and cosmetics to help your skin hold onto moisture. Moving into potential TMA, when mixed into wax and used as a stool softener, glycerin’s moisture-attracting properties attract water from the body which stimulates….movement.

More in line with what we might use it for, it is often incorporated into fondants to help keep them supple, and certain filings to keep them creamy and soft. And as an additive to truffle filling it might be great.

I think you might be seeing the issue.  If you were to put it into your chocolate, it may or may not seize.  It would probably depend on how much water it had previously absorbed.  But regardless would undoubtedly absorb moisture from the atmosphere and cause your chocolate to do really weird things.

It is also worth mentioning a few other things.  With most any substance, there are going to be a small number of people that have sensitivities or allergies to glycerin and it can be an issue if consumed in large quantities.  And it is worth noting that it is not calorie-free even though it is low on the glycemic index.. As a matter of fact, glycerin contains slightly more calories than sugar.  Unfortunately it isn’t as sweet (about 60%) so you are going to need even more to get the  same sweetness which is just going to compound the moisture issue.

And going back to the potential TMA, just as with sugar alcohols, consuming a lot of glycerin can produce a laxative effect which usually isn’t a thing most people look for in their chocolate.

So, here is a great example of ‘in theory it should work, but in practice it doesn’t’.  Sorry.  Good thinking though.