Dynamic changes in volatile organic compounds and microbial community of snakehead segments coated with a gallic acid–embedded edible film

This study aimed to investigate the dynamic changes in the flavor profile and microbial community of snakehead ( Channa argus ) treated with an edible coating during refrigerated storage at 4 °C. E -nose sensor data revealed that the raw samples exuded offensive odors with high levels of nitrogen oxides, methane, sulfur-containing compounds and terpenes after storage. Furthermore, the signals from gas chromatography–ion mobility spectrometry (GC-IMS) demonstrated that volatile organic compounds (VOCs) characterized by pungent odors, such as 1-octen-3-ol, served as spoilage markers. The edible coating containing gallic acid (GA) effectively suppressed the increase in the total viable count of fish samples. Specifically, GA limited the generation of spoilage markers by inhibiting the growth of specific spoilage organisms identified through microbial diversity analysis, including Shewanella , Acinetobacter , Psychrobacter . This inhibition likely resulted from GA's impact on bacterial membrane permeability and membrane potential. These findings demonstrated that GA–based edible coatings effectively suppressed spoilage bacteria and the formation of off-flavor compounds, offering valuable insights for preservation strategies in aquatic products.