Dietary corn germ containing phytic acid prevents pork meat lipid oxidation while maintaining normal animal growth performance
Presence of phytic acid in finishing pig diets may provoke a reduction in the oxidative processes in pork meat.
2007-10-25
Defatted corn germ meal (DCGM), which is a potential corn substitute in pig formulas,
is an industrial coproduct obtained after oil extraction that is relatively rich
in phytic acid (PA). The role of PA as an antioxidant in meat has been pointed
out in several reports and hence its role in the inhibition of lipid oxidation
is potentially crucial for retaining meat quality. The objective of the work was
to investigate the effect of endogenous presence of phytic acid, by the addition
of defatted corn germ meal to the pig diet, on animal health and thereafter on
the carcass characteristics and Longissimus dorsi lipid oxidation.A total of 24 (12 castrated male and 12 female) pigs were used with initial average weight of 70.8 kg. Animals were kept individually and they were allotted into four treatments (n=6) comprising a DCGM-supplemented diet at levels of 0%, 10%, 20% and 40% during the finishing phase. It was evaluated weight gain, ration consumption and feed conversion. Animals were slaughtered at the averaged weight of 91.2 kg and the carcass characteristic evaluated. Meat samples were evaluated for moisture, lipid, protein, ash content and lipid oxidation in samples stored for 7 days at 3o C.
No significant effect of the dietary treatments was observed in weight gain, ration consumption and feed conversion. In the same way the presence of DCGM in the diet did not affect pig carcass characteristics or chemical compositions of L. dorsi. However, there were effects of experimental treatments in lipid oxidation of L. dorsi, resulting in the addition of DCGM (indirect addition of PA) in lower lipid oxidation. The highest reduction was found when diet presented a 40% of DCGM, lipid oxidation in these animals was reduced by 63.0%.
This study demonstrates that phytic acid, endogenously present in dietary industrial defatted corn germ meal in the finishing phase, permits to maintain carcass characteristics and also permits a substantial inhibition of the meat lipid oxidation.