Influence of the commercial processing and floral origin on bioactive and nutritional properties of honeybee-collected pollen

Pollen is characterised for having a low fat content, a relatively high content of dietary fibre and an important amount of minerals and essential amino acids. With regard to bioactive compounds, honeybee-collected pollen exhibits an important source of phytochemical compounds and antioxidant activity. The purpose of this research was to study how the nutritional properties and the stability of the bioactive compounds found in honeybee-collected pollen were affected by the commercial processing and its floral origin. To achieve this goal, pollen pellets of different floral origin were harvested directly from hives and immediately stored at -80 degrees C. Pollen pellets were dried by placing them into hot-air chambers (traditional drying methodology) or by means of freeze-drying. We found a slight influence of floral origin on the nutritional properties of pollen pellets (multifloral pollen had higher contents of fat, carbohydrates, proteins and mineral elements than monofloral-type pollen), whereas the abundance of bioactive compounds was correlated with the origin factor as well as the methodology employed to dry the fresh pollen pellets, especially carotenoid pigments such as lutein (5.73 +/- 1.80, 4.93 +/- 1.16 and 0.81 +/- 0.16 mu g of lutein per g of pollen for fresh, lyophilised and hot-air-dried multifloral pollen).