Volatilome and Bioaccessible Phenolics Profiles in Lab-Scale Fermented Bee Pollen

Abstract

Bee-collected pollen (BCP) is currently receiving increasing attention as a dietary supplement for humans. In order to increase the accessibility of nutrients for intestinal absorption, several biotechnological solutions have been proposed for BCP processing, with fermentation as one of the most attractive. The present study used an integrated metabolomic approach to investigate how the use of starter cultures may affect the volatilome and the profile of bioaccessible phenolics of fermented BCP. BCP fermented with selected microbial starters (Started-BCP) was compared to spontaneously fermented BCP (Unstarted-BCP) and to unprocessed raw BCP (Raw-BCP). Fermentation significantly increased the amount of volatile compounds (VOC) in both Unstarted- and Started-BCP, as well as modifying the relative proportions among the chemical groups. Volatile free fatty acids were the predominant VOC in Unstarted-BCP. Started-BCP was differentiated by the highest levels of esters and alcohols, although volatile free fatty acids were always prevailing. The profile of the VOC was dependent on the type of fermentation, which was attributable to the selected Apilactobacillus kunkeei and Hanseniaspora uvarum strains used as starters, or to the variety of yeasts and bacteria naturally associated to the BCP. Started-BCP and, to a lesser extent, Unstarted-BCP resulted in increased bioaccessible phenolics, which included microbial derivatives of phenolic acids metabolism.

Changes in Phenols, Polysaccharides and Volatile Profiles of Noni (Morinda citrifolia L.) Juice during Fermentation

“…Esters play an important role in the flavor of juice [ 37 , 38 ]. In this study, the methyl hexanoate (with an odor threshold of 87 μg/L [ 39 ]) was found to be the quantitively predominant ester compound in fermented noni juice.…”

Bee Pollen: Current Status and Therapeutic Potential

“…They are efficiently utilized and a lot more affordable than previous techniques [13]. Various articles refer to fermentation using bacteria for exine dissolution such as lactic acid bacteria, Apilactobacillus kunkeei strains, and Hanseniaspora uvarum [18][19][20]. Enzymatic treatment is a valuable technique with promising results compared to fermentation as there are numerous enzymatic products commercially available at reasonable prices such as some papain, protamex TM , protease, neutral protease, cellulose, hemicellulose, or pectinase that allow the breaking of bee pollen wall down [13].…”

Multi‐host lifestyle in plant‐beneficial bacteria: an evolutionary advantage for survival and dispersal?

“…In this regard, nectar and pollen are a source of microbes for insect pollinators as high number of bacteria exist in floral nectar (up to 10 7 CFU/mm 3 ) and pollen (10 4 -10 7 CFU/g) (Liu et al, 2019). In fact, a significant number of bacterial taxa have been identified as common to honeybee populations and flowers, including different fructophilic lactic bacteria (Liu et al, 2019;Crovadore et al, 2021) a recently discovered group of heterofermentative bacteria that prefer fructose over glucose as a carbon source (Filannino et al, 2019). Yet, pollen and nectar often contain bioactive plant secondary metabolites (Schmitt et al, 2021) as well as agrochemicals that can alter the insect microbiome composition.…”