Pollen – benefits for bees & humans

Pollen is an extremely important part of honey bee nutrition and provides bees with proteins, vitamins, lipids, and minerals. The protein in pollen makes up most of the protein consumed by the bees. The many amino acids therein are vital for numerous functions in the bees’ bodies. The amino acids are classified into two groups: essential and non-essential amino acids. The essential amino acids are those that the bees cannot make, or synthesize, within their bodies. The non-essential amino acids are those that they are able to create through metabolic transformation or synthesis.

Pollen Forager Bees

Pollen is gathered by foraging honeybees and packed in the pollen baskets on their hind legs. A pollen pellet may weigh just 8 mg, sometimes more and sometimes less. With a single honeybee colony consuming between 12 and 34 kg of pollen per year, it is staggering to realise just how many foraging trips are needed to make up the total amount of pollen required. Pollen from different plants have differing nutritional value, containing more or less protein, and with different amino acids as constituents. In Ireland, we have a lot of plants producing high quality pollen. For example, various forms of clover (Trifolium spp.), oilseed rape (Brassica Napus), and the Rubus family, of which raspberries and blackberries are members.

Variety of pollen important for bees

Pollen gathered in spring has shown to have higher protein content than pollen gathered in summer and autumn. It is argued that the large amounts of pollen gathered in the spring and its higher protein content could be responsible for the large increase in brood rearing and population increase at that particular time of the year. Honeybees benefit greatly from having availability to pollen from many different sources. As described earlier, pollen from different plants contains different amino acids. Most do not contain all the amino acids needed by the bees.

If bees feed solely or predominantly on pollen from one type of plant, it could be feeding on pollen lacking one or several amino acids. This, in turn, could have implications for the functioning of the bee. It is largely recognised that the healthiest bees are those who feed on, and as larva were fed by bees who fed on, pollen from a multitude of different plants. They have a better immune system. And research has shown that bees parasitised by Nosema lived longer if they were fed multi-floral pollen as opposed to those who were fed mono-floral pollen. (With the exception of bees that were fed mono-floral pollen of very high protein content, who also tended to live longer.)

Quality or quantity?

Research indicates that bees are able to determine which pollen has better nutritional value, and if given a choice prefer protein rich pollen. However, this ability does not mean they only collect pollen with a high nutritional value. Instead of seeking out and collecting pollen with the highest possible nutritional value, honeybees put more emphasis on bringing in great amounts of pollen.

Research into pollen stress in honeybee colonies shows that whether colonies are deficient in either quality or quantity of pollen, their response to both stresses is to increase the total amount of pollen going into the hive as opposed to endeavouring to collect pollen of higher quality. Hence, if they have lots of pollen of varying quality, they can just consume more of the pollen of lesser quality to make up for its lower nutritional value. As discussed earlier, the quality, quantity and diversity of pollen are all important. Therefore, this approach appears to be a good way to ensure that the bees have the best chance of meeting their pollen needs.

Pollen increases lifespan of bees

The quality and amount of pollen, as well as the total amount of pollen protein, consumed by the bees at different stages of their lives are known to affect their life span. It also has a very important part to play in the bees’ ability to perform certain tasks. For example, foraging, dancing and nursing. (Nursing: both in relation to the functioning and development of the hypopharyngeal glands which produce Royal Jelly and Brood Food, and in the length and quality of the nursing carried out by the bees). Pollen is known to affect the bees’ development of the fat body which is essential for successful overwintering. Experiments during which bees have been fed pollen from certain plants has shown that the pollen from some plants are associated with longer lifespans.

Pollen is essential for larval development in bees

Availability of pollen is essential for good larval development. Nursebees (young adult bees) consume large amounts of pollen. The pollen is then turned into royal jelly and brood food in the hypopharyngeal glands and fed to larva.

Pollen stress on colonies with open brood that needs feeding can lead to lesser quality brood food and less frequent feeds of larva. It can also be responsible for early capping of larva and cannibalisation of younger larva. (The colonies tend to save the older ones that they have already invested a lot of energy into). Research has shown that adult worker bees who experience pollen stress as a larva have a shorter lifespan than those who do not. They also often weigh less and are smaller in size. Moreover, they are also less good at producing brood food and turn into foragers at an earlier stage. They are also generally less good at foraging than adult bees who were not exposed to pollen stress as a larva.

Bee Bread

Like nectar, fresh pollen will quickly spoil unless processed. The bees need to store pollen protein within the hive for use during times when fresh pollen is not readily available. Hence, honeybees will turn fresh pollen into Bee Bread through a process of lactic acid fermentation. Furthermore, the bees cannot easily digest raw pollen due to the hard cellulose shell surrounding it. When the pollen ferments the nutrients in it become available to the bees.

The bees make the bee bread, or ambrosia ‘The food of the Gods’, by packing pollen into cells. It is mixed with honey or nectar and bee saliva containing bacteria, yeasts and enzymes. The ratio is about 70% pollen, 25% honey or nectar and the rest bee saliva. This is sealed by a thin layer of honey. After this begins the process of fermentation which takes a few weeks. During fermentation the protein is broken down and its components become bioavailable.

Pollen stored as bee bread within the hive over winter retains much of its nutritional value. There is little deterioration in quality. However, the same would not be true for fresh or unprocessed pollen stored for that length of time.

Harvesting bee bread

Bee bread for human consumption is harvested in the autumn. The comb containing bee bread should be frozen straight away after harvesting. After a couple of days, the comb can be removed from the freezer and the bee bread removed from the comb, either manually or mechanically. It should then be picked over or cleaned. Clean and dry bee bread is then stored in an airtight glass jar in a cool, dark and dry place. Ideally in the fridge. Because bee bread is a fermented product it has a much longer shelf life than raw pollen. Up to 1-2 years. Bee bread has a similar fruity, earthy, slightly sweet taste as pollen, but with the extra sourness or tartness added by the fermentation.

When harvesting bee bread, it is advisable to take only what the bees can spare to make sure that they are not lacking in pollen or bee bread throughout the winter. There is often a good bit of pollen in the first super above the brood box. Unless you are leaving this box on over winter, the bee bread can be harvested from these. If you are harvesting bee bread to feed back to the bees, it can be kept frozen in the frames until needed. The frames can then be defrosted and inserted into colonies.

Bee bread for human consumption

People consume bee bread for a number of different reasons. As with many other honeybee derivatives, bee bread has been consumed since ancient times. It is thought to have many health benefits. For example antibiotic and antioxidant properties as well as boosting the immune system and fighting off disease. Whereas we are still waiting for much of this to be proven scientifically, the anecdotal evidence is pointing towards the many health benefits of eating bee bread for reasons other than its nutritional value.

Bee bread is reported to help create a healthy intestinal flora and helping with digestion and detoxification. It can also aid in boosting the function of many internal organs including the liver and increasing longevity. it has also been attributed with increasing energy levels, decreasing fatigue, and stimulating libido and fertility. In the area of cancer, it is thought to help to lower the risk of cancer, aid in the effectiveness of chemotherapy and slowing down tumour growth. Because of these factors and its reported antibacterial and anti-inflammatory effects, bee bread is getting a lot of attention as a health food but also from a medical perspective for its possible medicinal uses.

Harvesting bee pollen

Beekeepers can collect fresh pollen for both human consumption and for feeding back to bees. There is a growing market for pollen products for human consumption as a health food and performance booster. Both as bee bread and fresh or dried pollen. Bee pollen is highly nutritious. It not only contains many of the nutrients needed by the human body, there are also many health benefits reported as deriving from the consumption of bee pollen. Many of them are similar to those for bee bread as described above.

Most recommendations will advise to start with a few pellets of pollen or bee bread a day and increase the amount to one or a couple of tablespoons per day for maximum effect. (People allergic to honeybee products should not take pollen. Possible side effects include allergic reaction, phototoxic reaction, renal failure, and reaction with other medications.

Pollen traps

Pollen is collected using a pollen trap, which is a piece of equipment attached to the entrance of the hive. When foragers return to the hive after collecting pollen, they will walk through small openings. These openings are just big enough for the bee to get through, but strips the pollen from its legs. The pollen falls into a tray below and can then be removed and processed. When the day’s pollen collecting is done, slide out or lift the grille. This completely opens the entrance and allow unimpeded access for foragers and drones.

There are many different designs available on the market, but in essence they all work the same. The best ones are those where you can leave an unrestricted opening to the side allowing for drones to get in and out. (They do not fit into the small holes.) This also allows for foraging bees with pollen returning to that side of the entrance ensuring that some pollen keeps coming into the hive.

Collect responsibly

It is important to collect pollen responsibly. So be mindful of the long-term effects that pollen stress can have on honeybee colonies. Hence, pollen should be collected for only a couple of hours each day, and/or on alternate days. Collect pollen when you are certain that the colony has reasonable pollen stores and there is an abundance of available pollen. Do not collect during times of pollen scarcity either within the hive or in the available forage. Collecting pollen can be very interesting. It enables you to get a closer understanding of which flowers your bees visit for pollen. If you are investing in a pollen trap, I would advise that you also get a pollen identification chart. It will aid you in deciphering what plants your bees are foraging on using the colour of the pollen and the time of year as indicators.

Processing and storing bee pollen

Fresh pollen will spoil quickly and should be cleaned or picked over immediately after harvesting and subsequently frozen. Frozen fresh pollen is as close to fresh pollen as you will get. So if you are gathering pollen for personal consumption, it is best to keep in the freezer. Take out as needed and consume. Allow to defrost for 10-15 minutes before eating. Fresh pollen can be stored in the fridge for a few days and up to about two weeks. But it is best not to store fresh pollen for any length of time if avoidable. This is because the moisture in fresh pollen will encourage the growth of mould. Pollen for resale or for non-freezer storage should be dried.

The process of drying fresh pollen is as follows:

• Clean or pick over the freshly harvested pollen.
• Freeze for 1-2 days. Do not allow the pollen to form a clump in the container. Break up or shake if needed so that the pellets are frozen individually.
• Dry pollen at 35-40 degrees Celsius. A food dehydrator is best, but the oven on low heat, fan on and with oven door ajar will work well also. Spread out on a sheer cloth to allow air to reach all sides and dry the pollen until fully dry.
• If you want to clean the pollen further, you can set up a fan blowing at low speed and using two bowls. Pour the pollen from one into the other in front of the fan to remove pollen dust and chaff. Make sure to test first to ensure the fan is not too strong. If it is, you may end up with your precious pollen all over the place.
• Store in airtight containers in a dry and dark place, either cool or at room temperature. Stored like this, it will keep for a year or more.    

Feeding pollen or pollen substitute to bees

If you are collecting pollen to feed back to the bees, you can process it as above. Then mix with syrup to make pollen patties. These are usually made with a protein rich pollen substitute. Care needs to be taken when feeding pollen or pollen substitute to bees. It is important to make sure that the bees are ready for it and that the timing is right.

Pollen and/or pollen substitute are given to bees in order to encourage them to rear brood. They will recognise the increased availability of pollen and increase the rate of their brood rearing. The queen will lay more eggs and those eggs will turn into larva. The larva will need to be fed brood food by nursebees. These nursebees need to consume a lot of pollen in order to be able to produce the brood food.

Seasonal considerations

If this process is started too early, let us say late autumn or mid-winter, the extra bees created as a result of unseasonal brood rearing will often be superfluous to the requirements of the colony. They will turn into nurse bees at a time when not much brood is reared. They will need to consume a lot of pollen and honey or nectar. Moreover, they will have to leave the hive, and the cluster if one is formed, to defecate, during a time when the weather may not be suitable for them to do so. Pollen or pollen substitute should therefore be fed when it is desirable for the bees to start rearing brood. It can also be given to give them a boost when the availability of pollen is insufficient.

This in an extract from an article published in An Beachaire, The Irish Beekeeper, in February 2021