Efecto del aceite esencial de Lippia origanoides Kunth en la estabilidad oxidativa de huevos almacenados.

The aim of this work was to evaluate the inclusion of oregano essential oil (OEO) Lippia origanoides Kunth in diets enriched with poly unsaturated fatty acids (PUFA) on oxidative stability of eggs during storage. A total of 216 layer hens were randomly assigned of one of six treatments: 1) Basal diet with 2% of (Elaeis guineensis) palm oil (CONTP), 2) Basal diet with 2% of fish oil (CONT), 3) Basal diet with fish oil and 200 g/t of vitamin E (VITE), 4) Basal diet with fish oil and 100 g/t AEO (O100), 5) Basal diet with fish oil and 150 g/t AEO (O150), 6) Basal diet with fish oil and 200 g/t AEO (O200). At the end of the period, 14 freshly eggs from each replicate were collated, totaling 504 eggs. Seventy-two eggs were used to evaluate the initial state of the lipid oxidation and the remaining were storage at 4°C and -10°C, and analyzed for malondialdehyde (MDA) levels in yolk at 15, 30 and 60 days of storage. Data were analyzed as a completely randomized factorial design 6 x 2; Factor A dietary treatment, Factor B temperature (4°C and -10°C) with repeated measures of days of storage (15, 30 60 days). Tukey method was used to compared means (p<0.05). The effect of storage temperature showed that the MDA value was lower in the eggs stored at -10°C compared to 4°C. In both temperatures, the CONTP group exhibited the lower MDA value (24.1 and 28.4 ng de MDA/g of yolk, respectively). At 4°C, the treatments VITE, O150 O200 (38.7, 41.4, 38.6 ng MDA/g of yolk, respectively) showed similar (p>0.05) MDA value in egg yolk, showing better oxidative stability (p<0.05) compared to CONT and O100 (50.6 y 48.3 ng MDA/g of yolk, respectively). In the yolk of fresh eggs and stored during 60 days at 4°C, there was an inverse relationship between level of OEO in the diet and MDA concentration in the egg yolk (Y= 60.5 - 0.08 OEO; R2= 0.7028; p<0.0001 and Y= 47.3 - 0.09 OEO; R2= 0.8569; p<0.0001, respectively). It can be concluded that there is a clear oxidative stability effect of OEO supplementation in n-3 fatty acids enriched eggs during storage. [ABSTRACT FROM AUTHOR]