Evolution of bacterial growth in Melipona bicolor honeys after one year of storage

Guaraipo (Melipona bicolor) is a sting-less bee distributed throughout south and southeast Brazil, which is known for its honey production; however, it is not currently the target of much research. There are not many citations in the literature about the microbial activity of honey after storage, so the aim of this study is to elucidate this point by comparing the microbial condition of the product produced by sting-less bees after both 8 and 17 months of storage under refrigeration (4°C). With that in mind, the total and thermotolerant coliforms, mesophilic aerobic microorganisms, as well as yeasts and molds, were quantified in three honey samples collected in forest areas in the metropolitan region of Curitiba. No growth of total or thermotolerant coliforms was noted; however, it was possible to observe a decrease in mesophilic aerobes in the sample over the course of their storage. In the sample stored for 8 months, the counts were between 2.46 and 4.08 log CFU/mL; in the sample stored for ayear, these values were between 1 and 1.30 log CFU/mL or even no growth of mesophiles was observed. In addition, no growth of yeasts and molds was observed in the samples from 17 months of storage, with ≤ 1 log CFU/mL, unlike the samples stored for 8 months, which previously had both yeasts and molds, with counts ranging from 1.78 to 2.43 log CFU/mL. Although mesophilic, yeast, and mold growth were observed in the first instnace, we can conclude that after storage for a year in refrigerated conditions, there was a decrease in the bacterial growth found in sting-less bee's honey.