Características nutritivas de los hollejos húmedos de naranja (Citrus sinensis cv. Valencia) mantenidos en estibas

Proximate analysis and chemical characterization were done of humid orange peel (Citrus sinensis cv. Valencia) by-product immediately after industrial processing and during storage in piles for 12 d. Samples of the stored peel were taken on d 1, 4, 6, 8, 10 and 12 of storage from three layers within the piles: 5-15 cm, 15-30 cm and >30 cm. Results were analyzed with a completely randomized design, using a 3 x 6 factorial arrangement for temperature, pH and dry matter, and a 3 x 2 factorial for crude protein, calcium, phosphorus and ash. Analyzed factors were layer of pile, and sampling day. Interaction was found (P<0.01) between layer and day for dry matter, pH and temperature. The 30+ cm layer had the lowest dry matter values. Temperature was highest in the 5-15 cm layer, indicating fermentation to be most active in this layer. Values for pH initially decreased in the stratum 15-30 cm and 30+ cm layers, and then remained below 3.5. Overall, pH did not surpass 3.73. There was interaction (P<0.01) between layer and day for calcium and ash content, the latter indicating mineral loss over time. No interaction existed for crude protein and phosphorus, meaning there were no differences within layer and day. Humid orange peel by-product stored in piles did not exhibit variations in proximate composition or chemical composition that could affect it use as a livestock feed.