Valoración del orujo de aceituna en la alimentacion del ganado porcino. Efectos de la tecnología de secado

Resumen

El presente trabajo evalúa el valor nutritivo del orujo graso de aceituna para su utilización en alimentación porcina, considerando el impacto de diferentes tecnologías de secado y del tipo de subproducto generado en el proceso industrial. Se caracterizaron fisicoquímicamente diversos orujos obtenidos por secado en tromel, aire caliente y vapor sobrecalentado, analizando su composición química, fracción lipídica y digestibilidad in vitro de la materia seca. Asimismo, se estudiaron los subproductos de salida y ciclón del secado convencional, y se estimaron los niveles óptimos de inclusión y el valor económico del orujo en fórmulas comerciales para cebo porcino. Los resultados muestran que el secado con vapor sobrecalentado conserva mejor los ácidos grasos insaturados, mientras que el orujo ciclón presenta mayor digestibilidad energética. Se concluye que el orujo graso, especialmente el procedente de ciclón o secado con vapor, es un subproducto viable y económicamente eficiente en la formulación de piensos sostenibles para porcino.

ABSTRACT

This study explores the nutritional characterization and practical utilization of olive-pomace oilcake as a sustainable feed ingredient for grower-finisher pigs. The research investigates the impact of three industrial drying technologies—rotary drum drying, hot air drying, and superheated steam drying—on the physicochemical properties, lipid profile, and in vitro dry matter digestibility of olive-derived by-products. Detailed analysis was conducted on two fractions obtained from conventional drying methods (cyclone and outlet pomaces).

The findings indicate that while drying method did not significantly alter the proximate composition or digestibility coefficients, it markedly influenced the integrity of the lipid fraction. Superheated steam drying exhibited superior preservation of unsaturated fatty acids, notably oleic (C18:1) and linoleic (C18:2) acids, owing to reduced oxygen exposure. Cyclone pomace displayed higher lipid content and lower fiber-bound protein, enhancing its digestible energy value compared to the outlet fraction.

Moreover, linear optimization of commercial feed formulations demonstrated that olive-pomace oilcake can be included at levels of 15–20% without compromising energy density or amino acid balance. The utilization of cyclone-derived fractions enabled more cost-effective feed formulations. The integration of these by-products aligns with circular economy objectives by valorizing agro-industrial residues and reducing reliance on conventional raw materials.

In conclusion, olive-pomace oilcake—particularly from superheated steam-dried or cyclone-separated streams—offers both technical and economic advantages for sustainable pig nutrition.