Fat hardness and belly firmness decreased (P < 0.001) with increasing co-extruded flaxseed. Pigs fed co-extruded flaxseed levels had higher lean yield (P = 0.045) and total lean content (P = 0.034). Loin from barrows had higher fat content compared to gilts (P < 0.001). Co-extruded flaxseed supplementation increased (P < 0.001) omega-3 content in loin and ground pork. Pork flavour intensity and off-flavour intensity scores lowered (P < 0.001) with increasing levels of co-extruded flaxseed, being more accentuated (P = 0.023) in reheated pork chops from barrows. Diet affected all texture and flavor sensory characteristics (P < 0.05) as tissue levels of omega-3 fatty acids increased, likely as a result of increased lipid oxidation. On the other hand, feeding coextruded flaxseed to increase omega-3 fatty acid content in trimmed loin muscle did not result in levels sufficient to meet label requirements and had limited effects on palatability.
Flax co-extruded with peas did not provide sufficient antioxidant capacity to alleviate texture and flavor problems in high fat products with elevated polyunsaturated fatty acids content. Consequently, further studies should take into consideration that pork is typically marketed with some level of seam and/or trim fat.
M Juárez, MER Dugan, N Aldai, JL Aalhus, JF Patience, RT Zijlstra and AD Beaulieu, 2011. Food Chemistry, 126: 1716-1723.