The main aims of fermenting, pasteurising and conditioning are to make compost selective. This means that easily decomposable nutrients have been digested and competitor moulds have been destroyed or weakened.
It is customary nowadays to add a protein rich products to phase II or III compost to increase mushroom production. Actually quite a risky undertaking, as this can completely destroy the selectively in one go. In the first years when supplements were used, many serious blunders were also made. The current use of; selective and homogenously incubated compost; better mixing; heat and temperature treatment of supplements and purer supplements means that the risks today are very small. However, every so often I still see things going wrong and risks being underestimated. Bags get damaged and the supplement is often stored in damp conditions, which make an ideal home for moulds, mites and worms. Condensation in stock silos and supply lines can also cause lumps of supplement carrying unwanted guests.
The selectivity of any compost treated with this kind of supplement will be seriously affected. Stay alert! There’s good reason why compost is supplied selective.
Con Hermans, AdVisie ‘The mushroom cultivation advisers’ firstname.lastname@example.org