As the spirit chemist at Spiritopia Liqueurs, I have a vested interest in sugar. I also like it a little too much, like many others. Recently, there has been a lot of buzz about a new sweetener - coconut sugar (also called coconut palm sugar). It's a natural product made from the sap of the coconut palm by cutting the flower and collecting the juice. It's the tropical version of maple syrup. That's all fine but the interesting part is that it is claimed to have a low glycemic index. This is a measure of how much it raises your blood sugar. It is important for everyone, especially diabetics and pre-diabetics.
I bought a bag out of curiosity. The aroma is excellent with a warm, brown sugar note. The texture is coarse and the color variable as is typical for a less processed product. The taste is also very good. So the question is why would it be any lower glycemic than ordinary sugar?
This discussion gets a little technical so you may want to review my previous post on common sugar types if you don't remember the difference between glucose, fructose, and sucrose. Assuming we are clear on that, my first theory about the coconut sugar was that it was mainly fructose, like agave. The images below show that theory #1 does not hold water. I use liquid chromatography (LC) for distillery analytics. It separates mixtures into their components so you can quantitate each one. The first image shows a mixture of glucose and fructose being separated in time through the LC. The second image shows a typical agave syrup with a small glucose peak and a large fructose peak. The third image shows a solution of coconut sugar in red with a dashed line behind of the same concentration of pure sucrose. The result is interesting: the coconut sugar looks like the pure sucrose, except there is about 10% less of it. That would also reduce the glycemic index a little, but not the huge amount they claim.
So, theory #1 is dead and we move on to theory#2: the "other 10%" missing in the coconut sugar is something else that reduces or slows the absorption of sugar. That could be a real benefit. A couple reports suggest there is inulin in coconut sugar. This is a long chain of fructose molecules that we typically don't digest, although the bacteria in the lower gut do. It's in the group called prebiotics for that reason. In future posts, I will do a blood sugar test on myself to see if the claims work for me and also try to crack the inulin to verify its presence.