Drying and Processing Pollen

Pollen drying and processing means drying the moist fresh pollen taken from the trap at a low temperature, or freezing it, on the same day, then cleaning it and preparing it for storage, protected against pests. The quality of pollen is largely determined in the first hours after harvest. The right equipment is a dryer with a thermostat and fan, a freezer and simple cleaning sieves.

Why must pollen be processed straight away?

Fresh pollen in the trap drawer has a high moisture content (often above 20%), and the pellets contain sugar, protein and live microorganisms. In hot weather mould and yeast start to develop within a few hours; the pollen smells sour and the pellets stick together. Wax moth and other insects can also lay eggs in pollen that is left standing.

• Daily collection: The drawer is emptied every day, and twice a day in hot, humid weather.
• Same-day processing: Collected pollen is either frozen immediately or put in the dryer. Pollen left standing because "I'll see to it this evening" loses its best quality.
• Irreversible spoilage: Mouldy pollen cannot be put right by sieving or drying; it is thrown away entirely.

Drying or freezing pollen?

The Turkish Food Codex Communiqué on Bee Products (in Türkiye) requires fresh bee pollen to be kept at +8 °C or below from production until it reaches the consumer; dried pollen is exempt from this rule. If you intend to sell, decide from the outset in which form the product will be offered.

What types of pollen dryer are there?

• Drying cabinet with thermostat and fan: A cabinet with shelves, wire or perforated trays and a fan that circulates the air inside. It is the most reliable option in beekeeping and is available in sizes from small to commercial.
• Household food dehydrator: Works for small amounts of pollen. The temperature setting must go down to low values, and the actual temperature should be checked with a thermometer.
• Indirect solar dryer: A set-up in which sun-warmed air is passed over trays kept in the shade. The pollen does not see direct sun; temperature control is difficult because it depends on the weather.
• Freeze-drying (lyophilisation): The method that best preserves nutrients, but it requires expensive industrial equipment.

Drying in direct sun, in an oven or on a stove is not recommended: the temperature cannot be controlled, colour and aroma deteriorate, and the pollen is left exposed to dust and insects.

What should you look for when choosing a pollen dryer?

• Temperature control: The thermostat must be able to hold a steady temperature below about 40 °C. The temperature difference between trays should be small.
• Airflow: A fan and vents that expel moist air speed up drying; in a box with no airflow the pollen cooks but does not dry.
• Tray material: Stainless steel mesh or food-grade perforated plastic; the mesh should be fine enough that pellets do not fall through.
• Ease of cleaning: Inner surfaces and trays should be easy to remove and wash; pollen dust should not build up in the corners.
• Capacity: The dryer must be able to take all the pollen collected on the busiest day in a thin layer.

How do you dry pollen? Step by step

1. Pre-sorting: Remove by hand any obvious dead bees, large pieces of wax and leaves.
2. Thin spreading: Spread the pollen on the trays in a thin layer (a few pellets deep). In a thick layer the bottom does not dry.
3. Low heat: Set the dryer so that it does not exceed about 40 °C; the fan runs continuously.
4. Stirring: In the first hours of drying, stir the pellets gently a few times so that they do not stick together.
5. Dryness check: The time varies from a few hours to a day depending on the pollen's moisture and the dryer; check with the tests below.
6. Cooling: Let the dried pollen cool to room temperature in a closed but dry place; if it is put in a container while warm, moisture condenses in the container.

How can you tell pollen is dry?

• Finger test: A dry pellet does not squash when pressed between two fingers but stays hard; a moist pellet squashes like dough.
• Sound and flow: Dry pollen rattles slightly when shaken in a container and the grains flow freely; moist pollen clumps.
• Measurement: In commercial production, a moisture analyser is used. The target for dried pollen is for moisture to fall to single-digit levels; the limit value varies from country to country, so if you are going to sell, check the regulations in force.

Over-drying is not wanted either: the pollen turns to dust, breaks and loses colour and aroma. Insufficient drying, on the other hand, leads to mould during storage.

How is dried pollen cleaned and protected?

1. Sieving: The dry pollen is passed through a set of sieves that separates material larger and smaller than the pellets; crumbs and dust are removed.
2. Airflow: A gentle airflow (a fan or blower) blows away bee wings, hairs and dust; the heavier pollen pellets remain.
3. Final check: Any remaining foreign matter is removed by hand while looking over the tray.
4. Protection by freezing: Before packing, the cleaned pollen is kept in the freezer for a while (in most practice at least 48 hours). This is a common practice to neutralise the eggs of wax moth and other insects.
5. Packing: The pollen is put into dry, airtight, light-proof food-grade containers and labelled.

Hygiene and common mistakes

Pollen is a food that is eaten directly. The processing area should be clean and away from dust and pets; trays and sieves should be washed and dried after every batch. Workers wear clean overalls and, if necessary, gloves.

• Drying in the sun: The colour fades, the temperature rises uncontrolled, and the product picks up dust and insects.
• Spreading a thick layer: The top stays dry and the bottom moist; the bottom layer goes mouldy.
• Trusting the thermostat blindly: Check the actual temperature with a separate thermometer.
• Starting to sieve while the pollen is moist: The pellets are crushed and the sieve clogs.
• Mixing pollen from different days: A problem in one batch spreads to the whole stock; keep batches separate and labelled.