Sugar

You’ll get the best results with white granulated pure cane sugar. You can try substituting unprocessed sugar or artificial sweeteners, but expect quite different preserves from the ones I describe. Some recipes use honey as a sweetener; this is done because the flavor of the honey is welcome in those particular foods. Agave nectar makes a decent low-glycemic alternative to honey, so use that if you wish. Folks trying to limit their refined-sugar intake should check out books specifically written for them; a great one is Canning and Preserving without Sugar, by Norma MacRae (see Further Reading).