Nutrition Action had a chart a while back showing the % of fructose in common sweeteners, and all were 50%, plus or minus 2%, and the usual HFCS at 55%. But agave syrup had a whopping 88%! Yet they try to pass that off as the best sweetener for a diabetic to use, which is utter nonsense. It has a low glycemic index, but that is only one factor to consider. And rice syrup is almost all maltose, so we don't get any fructose when it is digested. But then, there may be arsenic...
One thing I found out recently on a bread baking forum was how the different sugars affect the different sourdough components - the wild yeasts and the lactobacilli - and that the fructose is what seems to feed the sour producing varieties of the lactobacilli. I figured this might explain Peter Reinhart's frequent use of agave syrup in his recipes, even though he never goes into detail about it. Either that, or he has stock in the companies.
