Sustainable cultivation of Pleurotus ostreatus : coffee grounds and grass residues as substrates

This study aimed to evaluate the cultivation of Pleurotus ostreatus (shimeji) on substrates based on coffee grounds and grasses—Zoysia japonica and Cynodon spp. cv. Tifton 85—and their mixtures. Substrates were formulated with 0%, 25%, 50%, 75%, and 100% coffee grounds in relation to each grass. Coffee grounds, grasses, substrates, and mushrooms produced were characterized for moisture, total solids, volatile solids, and fixed solids. Mushroom production was evaluated according to biological efficiency (BE). Substrates and their mixtures showed suitable physicochemical characteristics for mushroom cultivation; however, substrates composed only of grasses did not support fruiting. The highest BE—106.6%—was achieved with the substrate composed of 50% coffee grounds and 50% Z. japonica. Mushroom production had up to three fruiting cycles. Substrates with higher lipid content also produced mushrooms with higher lipid levels. The results demonstrate that using mixtures of coffee grounds with Z. japonica or Cynodon spp. cv. Tifton 85 is a technically viable and economically attractive alternative for P. ostreatus cultivation.