Fatty acid profile of wild edible and cultivated mushrooms (Pleurotus ostreatus, Amanita spp and Termitomyces microcarpus)

Abstract

Purpose The aim of this paper is to investigate fat content and fatty acid profile of cultivated (Pleurotus ostreatus) and wild edible mushrooms (Amanita spp and Termitomyces microcarpus).

Design/methodology/approach Pleurotus ostreatus was grown in soil and on cotton seed husks in mushroom growing rooms at Busitema University, Uganda. T. microcarpus and Amanita spp were collected from the wild. Freshly harvested mushrooms were dried at 60°C for 48 h in a hot air oven. Oil was extracted using a Clevenger apparatus. Fatty acid analysis was done using gas chromatography with flame ionization detection.

Findings Fat content ranged between 0.24 and 5.23 per cent. Variation was noted between P. ostreatus grown in soil and on cotton seed husks (p = 0.0090). Similarly, Amanita spp and T. microcarpus had differing fat contents (p = 0.0098). Polyunsaturated fatty acids (PUFA) predominated over saturated fatty acids (SFA) and monounsaturated fatty acids (MUFA). Linoleic acid (LA) was the most abundant fatty acid (FA) (30.91 to 54.35 per cent). It varied between Amanita spp and T. microcarpus (p = 0.0001) but not between substrates (p = 0.1891). Ratios of PUFA/SFA, MUFA/SFA and PUFA/MUFA were within the desirable ranges. Omega-6 FA/ω-3 FA ratio was higher than that recommended for a healthy diet. However, the low amount of fat in mushrooms suppresses the negative effects of a high ω-6 FA/ω-3 FA ratio.

Originality/value Information on FA profile of cultivated and wild edible mushrooms will provide a basis for commercial exploitation of the cultivated mushrooms. This work showed that P. ostreatus, Amanita spp and T. microcarpus are healthy foods with regard to the low fat content and high amounts of LA.