Use of propolis ethanolic extract as natural bee pollen preservative intended for human consumption

Abstract

We propose to evaluate the use of propolis as a preservative of fresh bee pollen intended for human consumption. A quantitative in vitro assay was performed to determine the antimicrobial activity of a propolis ethanolic extract over culturable heterotrophic mesophilic bacteria and molds and yeasts from fresh bee pollen during 22 days. The chemical characteristics of the propolis extract were also determined. The results of the quantitative antimicrobial assay showed that neither of the control treatments showed an inhibitory effect similar to the propolis ethanolic extract. The antimicrobial activity was due to the presence of bioactive compounds of propolis and not because of the alcohol present as a solvent. This is the first work that presents the combination of both bee products, propolis and pollen, in order to improve the conservation of fresh bee pollen avoiding the drying process. The results of the in vitro assay were encouraging as the antimicrobial action of propolis ethanolic extract against bacteria and molds/yeasts from fresh bee pollen was excellent.