Évaluation nutritionnelle du champignon Pleurotus geesteranus issu de différentes périodes de récolte

En culture hors-sol, plusieurs recoltes sont effectuees pour une production commerciale des champignons. Cependant, la qualite nutritionnelle reelle des fructifications apres chaque recolte sur le meme substrat reste encore meconnue. La presente etude a donc examine la composition nutritionnelle du champignon Pleurotus geesteranus sur trois recoltes. L’analyse nutritionnelle des echantillons a ete faite selon les methodes d’analyses standards. Les teneurs en proteines brutes, cendres totales, fibres bruts, sucres reducteurs et sucres totaux ont diminue significativement de la 1ere recolte a la 3eme recolte. En revanche, les teneurs en calcium, fer, lipide, humidite, vitamine C, glucides totaux et sodium ont augmente de maniere significative. D’autres composes comme les lipides bruts et la vitamine C ont augmente de la 1ere recolte a 2eme recolte puis ont baisse a la 3eme recolte. Les teneurs en glucides totaux, polysaccharides et sodium ont connu une evolution inverse. L’analyse en composante principale (ACP) des donnees physicochimiques ont permis de distinguer les champignons recoltes au 1er jour (PG1), au trentieme jour (PG2) et au soixantieme jour (PG3), tous independants les uns des autres. On pourrait ainsi dire que le champignon Pleurotus geesteranus conservent tout son potentiel nutritionnel et ce, quel que soit la recolte.Mots cles : Qualites nutritives ; composition chimique ; champignon Pleurotus geesteranus ; recolte periodique   English Title: Nutritional assessment of the mushroom Pleurotus geesteranus from different harvest periods In soil-less cultivation, several harvests are carried out for the commercial production of mushrooms. However, the actual nutritional quality of the fruiting bodies after each harvest on the same substrate is still unknown. This study therefore examined the nutritional composition of the mushroom Pleurotus geesteranus over three harvests. Nutritional analysis of the samples was carried out according to standard analytical methods. The contents of crude protein, total ash, crude fibre, reducing sugars and total sugars decreased significantly from the 1st harvest to the 3rd harvest. On the other hand, the contents of calcium, iron, lipid, moisture, vitamin C, total carbohydrates and sodium increased significantly. Other compounds such as crude lipids and vitamin C increased from the 1st harvest to the 2nd harvest and then decreased at the 3rd harvest. Total carbohydrates, polysaccharides and sodium levels showed the opposite evolution. Principal Component Analysis (PCA) of the physicochemical data made it possible to distinguish between mushrooms harvested on day 1 (PG1), day 30 (PG2) and day 60 (PG3), all independent of each other. We thus could say that the Pleurotus geesteranus mushroom retains its full nutritional potential whatever the harvest.Keywords: Nutritional qualities; chemical composition; mushroom Pleurotus geesteranus; periodic harvesting