A fortified syrup. Thin spring 1:1 recipe
12 # of cane sugar (3x 4#)
3 gallons hot tap water
2 Tbl Apple cider vinegar
1/2-1 tsp citric acid
1/4 tsp ascorbic or malic acid
1/4 tsp electrolyte/vitamin mix
Mix in thoroughly in 5-6 gallon bucket.
A primary reason for acidifying syrup is to “invert” the sugar. Cane sugar is pure sucrose. Sucrose is a 12 carbon sugar made up of two loosely joined six carbon sub-molecules (fructose and glucose). The acid disassociates the sucrose into the component parts, mimicking the nectar. This is termed by kitchen chemists “invert” sugar, and was used for baking. Most nectars (not all) are slightly fructose rich. The pH of nectar varies widely too (and many nectars, not co evolved with honey bees, have large components of indigestible (by bees) seven and greater carbon sugars. Practically, the sucrose sugar syrup can be inverted with vinegar or any other edible acid, and very little hydrogen ion donors are needed on the order of tablespoon per gallon. Ascorbic acid is made up of glucose (6 C sugar ring) with 2 carbon “tail” and various OH groups tagged to balance the Carbon charge. Many animals and their gut flora can synthesize this from any 6 carbon sugar source. A good reason to use at least some ascorbic acid (or tartaric) in the place of some of the simpler acids is ascorbic is a ring structure, while acetic (vinegar) is a simple unbranched chain. The ring is stable and “recycles” Hydrogen OH groups from solution. This means it is continually recovering donor potential and a little bit can invert an enormous solution much like a catalyst in reaction.
By using all various acids, you are feeding a more diverse and possibly more complete mix.
Source for acids: