Honey and natural syrups aren’t just sugar and water, there are also small amount of flavor molecule present. This is why honey from clover flowers tastes different than honey from wildflowers, which also tastes different than honey from pine flowers, etc. Also, this is why honey tastes different than maple syrup. If there weren’t flavor molecules, honey and syrup would differ only by relative sweetness.
These flavor differences could be just one or two molecules, but are likely several dozen to as many as hundreds. When discussing flavor, we usually use the expression “flavor profile” because it describes what is actually going on: flavor is the result of many different molecules and their relative levels of abundance.
Perhaos the most well know example of this is truffle oil, which is almost always made from synthetic truffle flavoring. When the food chemist’s do is find the most abundant flavor molecule, and produce it in a lab. There is absolutely no difference between the lab produced version and the natural version, except the lab only makes the one molecule and doesn’t recreate the entire flavor profile. This is why people often describe truffle oil as “flat” or “one-dimensional” because there’s literally only one flavor molecule activating your taste buds,and not the dozens to hundreds you are accustomed to
In addition to the flavor stuff, honey also has a water content of like 16%. It’s extremely dry compared to most other syrups. We use distillation to bring maple sap down to 33% water when we make it into maple syrup.
In general when cooking it’s easier to thicken a syrup by adding something that provides the additional viscosity than it is to remove water from something without burning it so most things we make have more water than honey does.
A piece that’s missing from the other comments is that there’s more than one kind of sugar. When we make sugar + water, regardless of water content, it’s pure sucrose.
Honey, maple syrup, corn syrup, etc. are all mixtures of various sugars (sucrose, glucose, fructose, etc.). So, in addition to any flavor molcules and other things, the actual chemical composition is different, so the properties & taste are also different.
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