QUALITY ATTRIBUTES OF PORK LOIN WITH DIFFERENT LEVELS OF MARBLING FROM DUROC AND IBERIAN CROSS

In the present study, the effect of marbling level of pork and the quality attributes of pork loins obtained from 42 pure Duroc x pure Iberian pigs (21 castrates, 21 sows) were studied. Generally, sex had less influence than degree of marbling on loin quality: results for physicochemical characteristics and color were similar for castrates and sows, whereas differences in marbling prompted significant differences (P < 0.05) for almost all parameters tested. Pressure-induced water loss, moisture, protein and ash content all increased as the degree of marbling decreased; by contrast, fat content, calorie content and color parameters L* and b* all rose with increased marbling. Quantitative descriptive sensory analysis showed that raw castrate loins displayed more marbling than raw sow loins; after cooking, however, both were similar in appearance. Aroma and taste properties were also similar after roasting, although there were sex-related differences in terms of texture. The panelist preferred the most heavily marbled loins. PRACTICAL APPLICATIONS The Iberian pork sector is increasingly making use of 25 and 50% Iberian x Duroc crosses, with a view to obtaining commercial hybrids providing improved productive traits compared with pure Iberian stock, with no loss of the rusticity and capacity for environmental adaptation characteristic of the Iberian pig; there is also no significant decline in intramuscular fat levels. Marketed Duroc x Iberian meat displays varying degrees of marbling, leading to variations in sensory attributes. This study defined differences in the sensory qualities of Duroc x Iberian pork loin as a function of three levels of marbling: slight, moderate and heavy.