Aproveitamento de resíduos agroindustriais na produção de rações para peixes onívoros.

Abstract

This research aimed to study the drying kinetics of three types of agroindustrial residues (pineapple, acerola and passion fruit), from the production of fruit pulps, to be used as alternative ingredients in fish feed. In order to do so, it was necessary to meet the following specific objectives: a) To study the drying kinetics of agroindustrial residues (pineapple, acerola and passion fruit) at temperatures 40, 50, 60 and 70 ºC and drying air flow at 1.5 m s -1, and to verify which of the mathematical models (Fick, Page, Cavalcanti Mata, Henderson & Pabis and Midilli), express better the experimental data; b) To prepare flours of the agroindustrial residues of pineapple, acerola and passion fruit and to determine the physical chemical analyzes (water content, crude protein, lipids, ashes, crude fiber, carbohydrates and energy) of these products; c) Study the shelf life in accelerated aging (temperature of 45 ºC), of four basic isoproteic and isocaloric rations processed at different drying temperatures (40, 50, 60 and 70 ºC), with protein and energetic levels for omnivorous fish, (pineapple, acerola and passion fruit), supplemented with soybean meal and wheat flour, determining their physico-chemical and microbiological analyzes for a storage period of 60 days. In this work it is concluded that the drying kinetics of pineapple, acerola and passion fruit residues can be better represented by the model proposed by Cavalcanti Mata with R2 ≥0.99 and DQM between 1.2 x 10-4 to 5.1 x 10-7 and it is verified that the effective diffusivity varies with temperature and can be expressed by the Arhenius equation from which the activation energy is extracted, obtaining for the pineapple by-products a value of 24.21 kJ mol-1, for acerola seeds of 21.58 kJ mol-1 and for the passion fruit residue of 21.967 kJ mol-1. The nutritional composition of the residues is in agreement with the literature and the Brazilian legislation. The four basic rations for fish manufactured and stored by accelerated aging at 45 °C for 60 days and physico-chemically and microbiologically evaluated practically did not change.