Quality attributes of lamb meat from European breeds: effects of intrinsic properties and storage

The sustainability of the European sheep farming sector can be ensured through the high and consistent quality of products, although the concept of meat quality, being multifaceted, is challenging to keep up by farmers and producers. The objectives of this study were (i) to evaluate quality attributes (CIE L*, a*, b*, lipid oxidation, cooking loss and Warner-Bratzler texture test) of lamb meat during cold storage originating from eight European breeds raised under their normal production systems (n=292 lambs); and (ii) to elucidate the influence of storage and intrinsic properties (cold carcass weight [CCW], ultimate pH [pH24], water activity [aw], and proximate composition) on the aforementioned quality attributes measured on the 3rd, 9th and 15th day post slaughter. All meat quality properties displayed a high variability due to the breed  production systems, although, as a whole, L*, a*, b*, TBARs and cooking loss increased during storage (P<0.001), whereas the tenderisation process was of non-linear decay nature (P=0.001). While production system – taken across breeds – was not found to affect meat cooking losses, it heavily influenced CCW, producing intensive systems heavier (P<0.001) carcasses (21.4 kg) than those raised in semi-extensive (14.9 kg) and extensive systems (13.8 kg). On the 15th day of storage, TBARs from intensive systems was significantly (P<0.001) higher than those of extensively raised lambs (0.839 mg MDA/kg vs. 0.299 mg MDA/kg, respectively). Although the extensive and semi-extensivesystems initially produced less tender meat (P<0.05) than intensive systems, on the 15th day of storage, meat from extensive (23.4 N/cm2) and semi-extensive systems (24.4 N/cm2) presented as good tenderness quality (P<0.10) as that of the intensive systems (22.1 N/cm2). Within breed × production systems, higher CCW or intramuscular fat was associated to darker meat (P<0.001 and P=0.014), higher redness (P<0.001 for both), greater lipid oxidation (P=0.016 and P<0.001), and lower slope (P=0.014 and P=0.004) and force (P=0.027 and P=0.001). The only intrinsic property that heavily affected most of the quality attributes was ash content, since meat of higher ash content presented higher luminosity (P=0.008), and lower redness (P<0.001), yellowness (P<0.001), TBARS (P<0.001), cooking loss (P=0.002) and tenderness (P<0.001). The elucidation of the impact of intrinsic properties on the lamb meat quality attributes during storage can help breeders and producers modify current flock management, feeding strategies and pre-slaughter and slaughter practices towards quality improvement or meeting particular consumers’ demands.