Efecto de lactosuero sobre Escherichia coli en el proceso de compostaje de residuos agroindustriales para evaluar la calidad microbiológica y agroquímica del compost

Abstract

The main objective of this research study was to evaluate the microbiological and agrochemical quality of compost through the effect of whey on E. coli in the agro-industrial waste composting process. Therefore, two Windrow compost piles were assembled from cow manure, bean, and corn wastes, each weighing 1 ton and with a percentage of 60% corn, 5% beans, and 35% cow manure. Pile 1 was initially irrigated with tap water and pile 2 with 50% whey. Characterization of raw materials was carried out through physicochemical tests such as pH and electrical conductivity; chemical tests such as dry matter percentage, C/N ratio, and organic matter percentage; and biological tests such as germination index. The piles were monitored daily through the determination of temperature, humidity percentage, and oxygen concentration, as well as the control of toxic parameters such as germination index and polyphenols. Finally, chemical parameters such as macro and micronutrients and microbiological monitoring of enterobacteria, coliforms, E. coli, and Salmonella spp. were analyzed throughout the process. The results obtained showed a descending microbiological growth, where the sanitization process of E. coli was variable during the composting stages. However, it was possible to obtain a compost that complied with the requirements established by the regulations of the European Commission to guarantee its safety when used as organic fertilizer in soils for agricultural purposes.