Transformation of agroforestry residues into food: productive, nutritional and educational evaluation of Pleurotus ostreatus cultivation in a technical education context

Abstract

This study evaluated the productive, nutritional and educational feasibility of cultivating Pleurotus ostreatus (oyster mushroom) using agroforestry residues as substrates within a technical secondary education context. Three substrate formulations were evaluated: pure poplar wood (A), poplar with wheat straw 50:50 (AT), and saligna with soybean hulls 70:30 (SS), with five replicates per treatment for productive variables and three biological replicates for protein concentration.

The AT substrate showed the fastest mycelial colonization (83.0 ± 3.1% at 35 days) and the shortest time to first harvest (6.6 ± 0.6 days). The A substrate exhibited greater sanitary stability and the highest number of harvests (3.0 ± 0.4). The SS substrate produced the highest protein concentration (2.71 ± 0.09 mg/ml), although it also presented a higher incidence of contamination. Statistical analyses (ANOVA and Kruskal-Wallis) revealed significant differences among substrates (p < 0.001 for most variables).

An economic estimation of the production system was also performed, projecting a monthly gross profit of $2,081,600 for a small-scale venture with 320 active bags per month. The project integrated concepts from microbiology, food analysis, sustainability and entrepreneurship, highlighting that oyster mushroom cultivation represents an effective pedagogical tool for linking applied science, circular economy principles and technical education.