Nutrients in edible mushrooms: an inter-species comparative study

A comparative study on various components of nutritional interest, such as water, protein, total amino acids, ash and minerals, in mushrooms of different species (Pleurotus ostreatus, Pleurotus eryngii, Pleurotus pulmunarius and Lentinula edodes) was carried out. Mushrooms were cultivated on the same compost (wheat straw added with 15% of sugar beet) and analysed immediately after harvest to avoid any interfering parameters. The limiting amino acid was also evaluated and the relevant protein chemical score was calculated. The moisture content of the edible mushrooms studied is high (ranging from 85.2 to 94.7%) and the ash contents range from 6.9 to 10.5% on a dry basis. Potassium is the most abundant mineral element followed by magnesium. Total nitrogen varies from 3.47 to 7.93% (dry basis), and P, ostreatus species has the largest variability among the samples analysed. The most abundant amino acids in mushrooms, expressed as percentages of total amino acids, are glutamic acid (12.8-20.9%), aspartic acid (9.1-12.1%) and arginine (3.7-11.7%), but in the analysed P. pulmunarius and L. entinus edodes a particularly low percentage of arginine (3.7 and 5.7%) has been detected. The chemical score generally ranges from 96 to 110%, the limiting amino acid being leucine or/and lysine. (C) 1999 Elsevier Science Ltd. All rights reserved.