Alongside syrup and pollen, additives are offered that are said to improve uptake, shelf life or effect of the feed.

The types

• Acidity regulators: Lower the pH of syrup, said to ease processing
• Preservatives: Against fermentation of syrup and mould on fondant
• Protein concentrates: As pollen substitute or supplement
• Flavour and attractant agents: To speed uptake
• Vitamins and trace elements

What it really comes down to

For a colony with varied forage and adequate stores these additives add little.

They only become meaningful where something is lacking — and then the first question is what is lacking and why.

Syrup fermentation

This is the problem that most often prompts an additive. Syrup left standing ferments, and fermented syrup burdens the gut.

The simplest solution, however, is not chemical: give quantities that will be taken up within a few days, and make syrup fresh.

Assessing critically

• Ask what research stands behind a claim
• Trial on a few colonies with untreated colonies alongside
• Check what is actually in it; some products are syrup with an additive
• Be cautious with products promising everything at once

The regulation

What is given to a colony can end up in honey.

• Products carrying a medical claim are veterinary medicines and fall under those rules
• Do not feed with supers on
• Record what was given and when

Where it goes wrong

An additive does not solve a problem whose cause lies elsewhere. A colony weakened by Varroa, damp or a failing queen does not improve from it.

Finding the cause comes before supplementing.