Selected-ion flow-tube mass spectrometry for the identification of volatile spoilage markers for fresh pork packaged under modified atmospheres

•Fresh pork spoilage was evaluated by microbial, chemical and sensory analyses.•Real-time mass spectrometry method development for monitoring volatolomic profiles.•Spoilage marker selection by instrumental data quality and multivariate statistics.•Acetoin (or ethyl acetate) was frequently identified under aerobic conditions.•Ethanol, 3-methylbutanal and sulfur compounds could indicate low-O2 storage process.