Effect of the shifting from multi-layer systems towards recyclable mono-material packaging solutions on the shelf-life of portioned semi-hard cheese

Packaging with recyclable plastic films could be an interesting alternative solution to extend shelf-life of portioned cheese. Two multi-layer materials of different types of one polymer (MonoMAP1 and MonoMAP2) with different barrier properties (O₂: 13 and 20 cm³(STP)/(m² × 24 h), 0 % RH; CO₂: 65 and 92 cm³(STP)/(m² × 24 h), 0 % RH) and coupled with modified atmosphere (MAP) were considered. Their performances in affecting cheese stability were compared to those of conventional multi-layer solutions under-vacuum (MultiVAC) and MAP (MultiMAP). Microbiological and physicochemical quality indicators were considered for a shelf-life study. In MonoMAP2, the initial loss of carbon dioxide and concomitant permeation of oxygen into the pack caused an earlier proliferation of molds with values of 4.7 log cfu g⁻¹, leading to its inapplicability. In the other packaged samples, the development of rancid volatile compounds resulted the more sensitive quality indicator to be used for shelf-life assessment, with a critical threshold perceived by panelists around 520 mg/kg. Cheese packaged in MonoMAP1 showed a shelf-life associated to rancidity development of about one third lower than that of MultiVAC and MultiMAP ones.