The process of pollen transformation into bee bread: changes in bioactivity, bioaccessibility, and microbial dynamics

Area of Science:

• Food Science
• Microbiology
• Biochemistry

Background:

• Bee pollen and bee bread are recognized for their health benefits.
• The biotransformation of pollen into bee bread, including polyphenol changes and microbial roles, is not fully understood.
• Limited data exists on polyphenol bioaccessibility and microbial interactions during bee bread fermentation.

Purpose of the Study:

• To evaluate microbial flora, antioxidant properties, and polyphenol/soluble protein bioaccessibility in bee pollen and bee bread.
• To investigate the impact of the harvesting period on these parameters.
• To elucidate the biotransformation process of pollen into bee bread under consistent apiary conditions.

Main Methods:

• Utilized an in vitro digestion model to assess bioaccessibility of polyphenols and proteins in post-gastric, serum-available, and colon-available fractions.
• Identified microbial flora, including lactic acid bacteria and yeast, using matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS).
• Employed Principal Component Analysis (PCA) to differentiate between pollen and bee bread samples based on harvesting periods.

Main Results:

• Bee bread exhibited greater polyphenol bioaccessibility compared to bee pollen from the same apiary.
• Key microbial species identified include Lactobacillus kunkeei, Leuconostoc pseudomesenteroides, and Candida magnoliae.
• PCA effectively discriminated between pollen and bee bread samples collected at different harvesting times.

Conclusions:

• The harvesting period significantly influences polyphenol bioaccessibility in bee bread.
• Microbial fermentation plays a crucial role in enhancing the bioaccessibility of beneficial compounds in bee bread.
• This study provides novel insights into microbial dynamics and bioaccessibility during the biotransformation of pollen to bee bread within the same beehive.