Effect of exposure to light on physico-chemical quality attributes of sliced dry-cured Iberian ham under different packaging systems

Dry-cured Iberian ham slices were stored under vacuum and under two different atmospheres (N2 = 70% N2 + 30% CO2; Ar = 70% Ar + 30% CO2) and exposed to lightness or darkness. Physico-chemical, sensory and microbial analysis was carried out throughout 60 days storage. Vacuum samples showed the highest a*-value compared to N2 and Ar after 30 (P < 0.05) and 60 days (P < 0.05). The influence of illumination during storage was evident after 60 days of storage, L* and a*-values being lower (P < 0.01) in hams exposed to light than those kept in darkness, which can be ascribed to the lower nitrosylmioglobin content in samples exposed to light after 60 days (P = 0.001). Ham slices stored in darkness showed the lowest TBARS values (P < 0.05) and hexanal content (P < 0.05) after 60 days. Slices of ham packed in vacuum showed lower TBARS values than N2 and Ar batches (P = 0.001), these samples being perceived as more rancid (P < 0.05). The rest of the sensory attributes were not generally affected by gas mixture or illumination (P > 0.05).

► Redness and white colour of fat are best maintained by vacuum packaging rather than in MAP. ► MAP Iberian ham slices are perceived as more rancid than in vacuum conditions. ► Samples kept under illumination show a higher rancidity. ► Vacuum is the most suitable system to prolong shelf life of slices of Iberian ham.