Designing a modified atmosphere packaging (MAP) for fresh-cut artichokes

‘Catanese’ artichoke quarters were packaged in active modified atmosphere (5% O2+10% CO2) in four different materials or in air in macro-perforated bags used as control (CTRL), and stored at 4°C. Materials used for modified atmosphere packaging (MAP) were: polylactic acid (PLA), polylactid acid with one line of micro-perforation (PLA MF1), polypropilene with two lines of micro-perforations (PP MF2), and polypropylene + polyamide with two lines of microperforations (PP+PA MF2). Initially and after 2, 4, and 9 days, overall artichoke appearance, color and weight loss were monitored. O2 and CO2 concentrations within the packages were detected initially and after 1, 2, 17, 24.5, 41.5, 49.5, 120 and 216 h (end of the experiment). Also, at the last sampling date ethanol and acetaldehyde accumulations in artichoke tissue were measured. All the micro-perforated films maintained gas levels within the range of O2>3% and CO2<15%, defined as “safe”, with a positive effect on quality: all samples remained above the limit of marketability until the end of the experiment, without significant differences among them, but showed a slight better overall appearance and, accordingly, a better retention of color parameters when compared with CTRL samples. Complete anaerobic condition (16% CO2 and 0% O2) developed in PLA bags where blackening of cut bracts and receptacle was observed, while black spots appeared on outer bracts, causing drastic quality reduction; samples fell below the limit of marketability after just 2 days. Also a significant accumulation of ethanol and acetaldehyde was found in these samples. Optimizing MAP made it possible to maintain the desired gas condition, with positive effects on quality of the produce in absence of any stabilizing treatment, for 9 days.