Hydrated Lime for Cold Pasteurisation

Hydrated lime (calcium hydroxide) is an effective, low-cost method for cold pasteurising bulk substrates such as straw, sugarcane bagasse, or cardboard for mushroom cultivation. By soaking your substrate in water with the correct concentration of hydrated lime (2 g per litre water), the high pH environment created kills or suppresses competing moulds, bacteria, and other contaminants – all without the need for heat or specialised equipment. This method is especially effective for oyster mushroom cultivation, offering a fast, energy-saving alternative to hot water and steam pasteurisation.
Tip: Always wear gloves and eye protection when handling hydrated lime, and measure carefully to maintain effective yet safe pH levels.