Design of the correct modified atmosphere packaging for fresh-cut broccoli raab
A low-oxygen controlled atmosphere has been reported to be useful in maintaining freshness and qualitative traits of fresh-cut broccoli raab during cold storage, while excessive accumulation of CO2 (10-15%) should be avoided. Starting from these previous findings, the aim of this work was to select the correct modified atmosphere packaging (MAP) for fresh-cut broccoli raab in order to reach, at equilibrium, the target low-oxygen (3%) atmosphere during cold storage. Broccoli raab harvested from a commercial farm was sorted to remove defects and cut from the stalks, obtaining the ready-to-use product. After washing, the product was packaged in plastic trays sealed in bags of different plastic materials. Two commercially available polymeric laminated films [polypropylene/polyethylene terephthalate (PP/PET) and microperforated polypropylene/polyamide (PP/PA)] were used with or without the inclusion of a CO2 absorber (5-g sachet). For each package type, a passive atmosphere (P-MAP) and an active atmosphere achieved by flushing with 5% O2 in nitrogen (A-MAP) were used. Unpackaged samples were used as controls and stored with all packages at 5°C. Quality attributes (overall appearance, odor, color, and weight loss) were evaluated initially and after 3 and 8 days. Gas concentrations (O2 and CO2) inside packages were also monitored. Among the packaging treatments tested, the combination using PP/PA in A-MAP with the use of CO2-absorbing sachets reached an equilibrium condition very close to optimal for broccoli raab (5% O2 and ≤5% CO2). Fresh-cut broccoli raab stored under these conditions for 8 days showed negligible reduction of appearance and odor scores, and product was comparable to the fresh samples.
Cefola, M., Amodio, M.L. and Colelli, G. (2016). Design of the correct modified atmosphere packaging for fresh-cut broccoli raab. Acta Hortic. 1141, 117-122
Brassica rapa L., controlled atmosphere, high CO2, off-odor