Growth of morel mushroom mycelium in cheese whey

Abstract

SummaryCheese whey was used as substrate for submerged cultivation of 8 strains of 6 species of edible mushrooms (morel mushroom):Morchella crassipes(3 strains),M. angusticeps, M. rotunda, M. deliciosa, M. esculentaand an unidentifiedMorchellasp. Best growth of morel mushroom mycelium was obtained with one of theM. crassipesstrains. The optimum growth conditions for the selected mycelium were as follows: initial pH, ~ 5·0–5·5; temperature, 25–28°C; inoculum size, 150–250 mg mycelium/100 ml whey; N sources: peptone and yeast extract; trace elements: K and Fe. More than 20 g/l mycelium was harvested in the form of pellets. Some growth kinetics studies were also performed. The initial carbohydrate (lactose) content was reduced from 5 to 0·4% at the end of the cultivation period. The specific growth rate ofM. crassipesATCC 13227 was from 1.0 to 6·4 x 10–2, depending on the growth phase. The harvested biomass contained about 45% protein, 5% fat and 8·5% ash (on a dry-weight basis). Essential amino acid content was comparable to the FAO standard, except for methionine, and unsaturated fatty acids predominated in the fat. The results with whey are compared with previously reported data on morel mushroom mycelium growth on waste sulphite liquors.