How long can I store fully colonised grain spawn?
Use grain spawn as fresh as possible, ideally within 2-4 weeks of full colonisation. For short storage, keep at 2-6°C in the fridge, (upright and ensuring dry filters). Quality signs: white, firm grains, no sour smell or pooling. Each extra week can reduce vigour, so expect slower colonisation and higher contam risk over time. Avoid freezing. If you see off-odours, wet spots, or colour changes (non-metabolite), discard. For longer-term storage, keep master plates/slants and make fresh grain spawn on demand.
