APROVECHAMIENTO DE SUBPRODUCTOS CÍTRICOS: FERMENTACIÓN DE LA CORTEZA DE NARANJA POR ASPERGILLUS NIGER VAN TIEGHEM, 1867

Abstract

The use of citrus by-products was evaluated through the fermentation of the orange peel by means of Aspergillus niger van Tieghem strain, 1867, which was obtained by inoculation in a petri dish, at a temperature of 35°C and a pH of 4,3. The crushed orange peel was used as a substrate, partially dehydrated, spread on trays, dried in cardboard trays and without heat pretreatment, adding only components and mineral nutrients, and A. niger was cultivated at different fermentation temperatures between 8°C and 40 °C. Upon completion of the fermentation process of the pretreated orange peel, maximum percentages of transformation of mineral nitrogen to organic nitrogen of 34.5% were obtained, for a value of the thermal integral between 0°C and 320°C per day, obtaining for a kg of dry matter, 6.6% protein for 600 g of product (feed) with 18% protein. Finally, the variation of the pH of the substrate was correlated as a function of the thermal integral of the crop; the performance of the transformation of mineral to organic nitrogen as a function of the thermal integral of the crop and the evolution of the organic nitrogen content of the orange substrate fermented by A. niger compared to the thermal integral. The results show high correlation coefficients. It is concluded that it is possible to take advantage of citrus by-products by fermentation of the orange peel by A. niger .