Drone Brood Homogenate (Apilarnil)

Apilarnil is a bee product made by crushing drone larvae together with the food they lie in into a homogeneous mixture; in the literature it is also referred to as drone larva homogenate. Its raw material is drone brood that is cut out and thrown away anyway as part of varroa control. Producing it requires the right harvest timing, strict hygiene and an unbroken cold chain; knowledge of its effects on human health, however, is still limited.

What is apilarnil, and where does the name come from?

Apilarnil is a light cream-coloured, thick product prepared by collecting young drone (male bee, drone brood) larvae together with the food in their cells and homogenising them. The product was first described by the Romanian researcher Nicolae Iliesiu; the name combines the syllables api (bee), lar (larva) and nil, derived from the researcher's name.

Because it spoils very quickly when fresh, it is found on the market mostly in frozen form, as a freeze-dried (lyophilised) powder, or mixed with honey.

Why drone larvae?

The varroa mite strongly prefers drone brood over worker brood for reproduction. That is why, in spring and early summer, beekeepers give the hive drone comb (a drone trap frame), let the bees rear drone brood in it, and after the brood is capped cut the comb out to remove the mites from the hive.

This cut-out brood is usually thrown away. Apilarnil is based on the idea of making use of the same material: when planned properly, production can be a by-product of varroa control without putting any extra burden on the colony.

When is apilarnil harvested?

Drone development from egg to adult emergence takes about 24 days: about 3 days as an egg, 6–7 days as an open larva, then the pupal stage in a capped cell. The target stage for apilarnil is when the larvae are about seven days old, that is, around 10 days after laying, when the cells begin to be capped.

At this stage the larva is large, soft and glossy white, and there is still some food in the cell. If taken later, the larva begins to turn into a pupa and the composition and consistency of the product change. If taken earlier, the larvae are small and the yield is lower.

To obtain larvae of the same age, note the date the queen lays in the drone comb; if necessary, check the frame a few days later to pin down the day laying began.

How is apilarnil prepared? Step by step

1. Give the drone trap frame: give a strong, healthy colony a drone comb, or an empty frame with foundation only on the top bar; the bees will build drone cells in the lower part.
2. Record the date: note the day the queen starts laying in the drone cells.
3. Remove it on time: about 10 days after laying, as the larvae begin to be capped, take out the frame and brush off the bees.
4. Work in a cool place: take the frame straight to a cool, clean processing area; open the capped cells with a knife or fork.
5. Remove the larvae: the larvae are taken out together with their food using tweezers, a small spoon or a vacuum collector. Larvae that have moved into the pupal stage, changed colour or show signs of disease are set aside.
6. Homogenise: the collected mass is blended into a smooth mixture in a clean blender.
7. Strain: wax fragments and coarse particles are removed by passing it through a fine strainer.
8. Chill immediately: without delay, the product is divided into small containers and frozen or sent for freeze-drying.

How is apilarnil stored? The cold chain

Like royal jelly, apilarnil is very prone to spoilage. Because of its high water and protein content, it spoils quickly at room temperature and changes in smell and colour.

• Keep it cold from the moment of collection: have a cool box ready at the apiary and a refrigerator in the processing area.
• Freeze for long-term storage: store at −18 °C or below, divided into portions.
• Drying option: freeze-dried powder keeps better because the water has been removed; even so, it must be protected from moisture, light and heat.
• Container: use dark-coloured, airtight, food-grade containers.
• Do not refreeze: thawed product must not be frozen again.

What should you watch out for regarding varroa and residues?

Drone brood is where varroa is found most. In frames from which larvae will be taken for the product, the presence of mites must be taken into account. Mites can get into the product when the larvae are removed; product should not be taken from heavily infested frames, and straining and sorting must be done carefully.

• Timing: for the drone trap frame to serve its varroa purpose, it must be cut out after the cells are capped and before the drones emerge. Leaving the frame in the hive for the sake of collecting product lets the mites multiply and spread through the colony, reversing the method.
• Treatment residues: varroa treatments must not be used in a colony producing apilarnil during the period the product is taken. The comb and foundation used must also be made of residue-free wax.
• Disease: no product is taken from a colony showing signs of brood disease.

What is known about apilarnil?

Apilarnil is a much less researched product than honey, pollen and royal jelly. Studies of its composition report that it contains protein, amino acids, fats, sugars, vitamins and minerals, while some studies report low levels of hormone-like compounds. The composition varies with the age of the larvae, the nutrition of the colonies and the way it is processed.

Reliable evidence on its effects in humans is limited. For this reason, no disease-treatment or health claims should be made when promoting the product; therapeutic claims on food products are prohibited in most countries. It should also be remembered that people allergic to bee products may react to it.

Before you start producing apilarnil

• Research the market: apilarnil is not as well known as honey or pollen; clarify your sales opportunities beforehand.
• Set up the cold chain: don't start production without freezer capacity and cold transport.
• Learn the regulations: find out about food business registration, labelling and sales rules from the local agriculture authority.
• Keep records: the colony, laying and harvest dates, quantity and storage conditions should be recorded for every batch.