Chemical composition and content of free tryptophan in Slovenian bee pollen

Bee pollen is a good source of different nutrients that are important for humans. The composition varies depending on its botanical origin, region and country. The aim was to characterize, for the first time, bee pollen from Slovenia. Thirty-two samples of bee pollen were collected during the 2014 season. Contents of water, protein, fat and ash were determined, and the total carbohydrate content and energy value were calculated. Sixty-five different botanical families or species were identified in these samples. Fresh Slovenian bee pollen contained on average 227.3 g.kg(-1) of water, 174.6 g.kg(-1) of proteins, 73.6 g.kg(-1) of fat, 20.6 g.kg(-1) of ash, and 503.8 g.kg(-1) of total carbohydrate, with an average energy value of 14.3 MJ.kg(-1). Our data were compared with similar studies and with a draft for the international basic composition requirements for bee pollen in human nutrition. Significant differences were obtained between fat content and energy values across the different months of bee pollen collection. The free tryptophan content was determined in eight unifloral bee pollen samples, and was found to range there from 0.028 g.kg(-1) to 0.197 g.kg(-1) fresh weight. These data serve as an indication of the nutritional quality of Slovenian bee pollen.