Morel Mushroom Mycelium Growth in Waste Sulfite Liquors as Source of Protein and Flavouring.*

Abstract

Three species of morels (Morchella spp., Morchella crassipes and Morchella esculenta) were cultivated in the waste sulfite liquors (Mg-base and NH3-base)-ammonium phosphate dibasic-corn steep liquor media. The spectrum of essential amino acids is comparable to the FAO standard, except for the levels of methionine and isoleucine. The gas-liquid chromatogram shows the presence of all essential fatty acids including palmitic, stearic, oleic and linoleic acids. All amino acids and fatty acids present in the fruiting bodies of the meadow mushrooms (Agaricus bisporus) were found in the samples of morel mushroom mycelium (MMM) grown in waste sulfite liquors (WSL). A strong mushroom flavour (aroma and taste) is also conserved in the freeze-dried powdered samples. The flavour concentrate of Morchella crassipes grown in NH3-WSL is recovered and compared with that of the meadow mushroom using gas-liquid chromatography, infrared spectrophotometry and ultra-violet absorption spectrophotometry. The flavour concentrates prepared from the freeze-dried samples lack low boiling compounds, while they are richer in high boiling components. Tentative interpretation of the infrared spectra revealed the presence of ketones, aldehydes, alcohols, phenols and esters in all flavour concentrates.