Impact of Storage Conditions on the Stability of the Physicochemical and Microbiological Characteristics of Animal Feed Made from Fish Waste

Background: This study was conducted to evaluate the effect of storage time and temperature on the stability of the physicochemical and microbiological characteristics of animal meal derived from fish waste collected in the northern central region of Algeria (fisheries of Algiers and Boumerdes). Methods : The obtained meal sample was stored in the refrigerator, at room temperature and in an oven at 55oC for 7, 15 and 21 days. The analyses were performed at the Laboratoire National de Contrôle et Analyse des Produits de la Pêche et d’Aquaculture et de la Salubrité des Milieux (L.N.C.A.P.P.A.S.M) in Algiers. Result: The results on the fresh meal reveal a satisfactory physicochemical composition, with a pH close to neutrality and low humidity, but high levels of ash and fat. After the storage period, it was observed that keeping the flour at low temperatures helped preserve its quality better. However, refrigeration allowed for the stabilization of humidity and lipids, while limiting microbial proliferation. Conversely, high temperatures (55oC) promoted the degradation of nutrients, especially in the case of prolonged storage, thus increasing the risks of lipid oxidation and protein degradation. The microbiological results indicate significant contamination from the outset, particularly from the total aerobic mesophilic flora as well as yeasts and molds. These results underscore the importance of strict control of technological processes to ensure the nutritional and hygienic properties of flour made from fish waste.