Volatile composition changes of fruits in a biopolymer-coated polyethylene active packaging: Effects of modified atmosphere and packaging-shaped bacterial community.

The potential impacts of active packaging on the volatile composition of fruits during preservations largely associated with consumers' acceptance, yet was barely investigated. In this work, a biopolymer-coated polyethylene active film was developed and its effects on qualities and volatile compositions of fruits with different respiration rates were comprehensively investigated. Underlying reasons for the effect of active packaging on volatile composition change of fruits were elucidated through revealing ternary relationship among the packaging-shaped bacterial community, modified atmosphere and volatiles. Off-flavor production was reduced and more sesquiterpenes (α-cubebene, copaene, β-caryophyllene, α-caryophyllene, d-amorphene) were reserved for longan packaged with active film, due to its antimicrobial and moisture absorption ability, as leading contributors to the selective inhibition on spoilage bacteria genera including Zymobacter, Gluconobacter and Pantoea. Whereas volatile profile of strawberry with high respiration rate was more actively affected by the modified atmosphere induced by packaging, instead of the bacterial community, where hypoxia (<2% O) led to the accumulation of ethyl esters (0.154-0.184 μg/g) that conferred off-flavor but decreased production of methyl (0.172-0.367 μg/g) and hexyl esters (1.26-1.89 × 10 μg/g) that represented typical fruity aroma. This work adds new knowledges on impacts of active packaging on the volatile profile of fruits and would provide guidance to smart design of active packaging for preservation of aromatic fruits.