Microbiological characterization of food residues for animal feeding

Abstract

A description is offered of microbiological characterization of the biodegradable fractions present in food wastes so that those fractions can be transformed in such a way that they will fulfil the specifications involved in their use as raw materials in other production areas. In this way the wastes can be converted into sub-products, hence minimizing the amount of them eventually sent to rubbish dumps. Of all the types of residues analyzed, only those obtained by separate collection from fishmongers' and greengrocers' sections of large supermarkets and small shops were valid for the objectives of the project and were subjected to a heat treatment to test whether or not this treatment was capable of reducing their microbiological content to the point of converting them into acceptable raw materials for animal feed. Residues from butchers' sections of supermarkets and small shops, and residues from restaurants were not included in the final study because of the prohibition by the European legislation in force of using any kind of meat containing wastes for feeding farm animals. In the present work we made a one-year analysis of representative samples of such wastes. We observed that after thermal treatment at a temperature of at least 65 °C for 20 min the nutritional and microbiological parameters remained suitable for their possible use as animal feed and that their harmlessness was ensured, with no loss of nutritional characteristics. Regarding the microbiological study of the meals which have been obtained from residues for the production of the feed and the feed itself, and in accordance with the data for nutritional composition, we consider valid and sanitarily adequate their use as animal feed with the concomitant consequent minimization of waste, which has become a priority in view of the recent legislation enacted by the European Union.