Impact of consumer handling on bacteriological quality of orange and red grape juices

This study examined if the direct consumption of fruit juices from the juice packs, at intervals and irrespective of storage conditions between the consumption, could predispose fruit juices to bacterial contamination and consumers to health risks. The test group consumed either orange or red grape juices directly from the juice pack at 3-h intervals for a 6-h drinking regime, while storing the juices at ambient conditions or 4 °C. Control juice had no direct contact with the consumer’s mouth. Total bacterial counts (TBC) in the juices consumed directly from the packs and stored at ambient temperature were higher than TBC observed in the juice samples of one consumer. The 16S rRNA sequencing analysis of selected isolates revealed potentially pathogenic bacteria sharing similarities with Bacillus amyloliquefaciens, B. atrophaeus, B. cereus, B. subtilis, and B. tequilensis. Some of the identified strains exhibited amylase and hemolytic potentials in vitro, while eae gene, coding for adherence factors mostly in Escherichia coli, was detected in one strain of B. amyloliquefaciens in this study. Consumers are advised to pour juices into pre-washed cups before the consumption, and to store leftovers at 4 °C or even lower.