Decolouration and lipid oxidation changes of vacuum-packed Iberian dry-cured loin treated with E-beam irradiation (5 kGy and 10 kGy) during refrigerated storage

Abstract

The effect of irradiation (0, 5 and 10 kGy) on the oxidative and colour stability of vacuum-packed Iberian dry-cured loin slices from pigs fed on concentrate feed (CON) or free-range reared (FRG) stored under refrigerated storage was studied. Irradiation treatment increased lipid oxidation, measured as TBA-RS values and hexanal content of dry-cured loins. It also increased redness (CIE a*) and lightness (CIE L*) of dry-cured loins. Refrigerated storage reduced the differences due to irradiation treatment of instrumental colour values like lightness. However, the decrease of redness during storage was more marked in irradiated than in non-irradiated dry-cured loin. Storage increased differences in TBA-RS values between irradiated and non-irradiated FRG dry-cured loin, while the opposite trend was found for CON dry-cured loins. In addition, no differences in the hexanal content were found after 30 days of refrigerated storage. Therefore, the storage of Iberian dry-cured loin in absence of oxygen by using a vacuum packaging could be an adequate method to reduce changes associated to irradiation treatment in Iberian dry-cured loin. Industrial relevance: Iberian dry-cured loin is a high sensory quality meat product with increasing projection in external markets Irradiation has shown to be an effective method to control pathogen and spoilage microorganisms in meat and meat products. However, e-beam irradiation can promote colour and oxidation changes that could modify their sensory characteristics. The study aimed the evaluation of e-beam irradiation at two levels (5 and 10 kGy) - higher doses than those that could be necessary to control pathogen microorganisms in this kind of product - on colour changes and lipid oxidation at vacuum-packed slices of Iberian dry-cured loin during subsequent extended chilled storage. E-beam treatment induced changes in colour and lipid oxidation in sliced Iberian dry-cured loin immediately after treatment and subsequent refrigerated storage. © 2009 Elsevier Ltd. All rights reserved.