Topical Area: Nutritional Microbiology, Dietary Bioactive Components
Objectives : To determine the effects of sun drying, oven drying,microwave drying and deep frying on the nutritional composition and phytochemical screening of the mushroom, to evaluate the most appropriate method for preservation and to extensively study the nutritional analysis of the various drying methods.
Methods : The proximate parameters: moisture content, ash content, crude protein, lipid/fat content, crude fiber, carbohydrate content, dried and matter were screened in all samples. Phytochemical screening for alkaloids, carbohydrates, glycosides, proteins/amino acids, flavonoids, steroids, terpenoids, tannins, saponins and phenols was evaluated. Mineral content, sodium and potassium were determined.
Results : Result from each sample showed; moisture content (88.96%, 21.09%, 23.30%, 13.24% and 0.96% respectively), ash content(0.89%, 8.40%, 7.80%, 5.34% and 4.20% respectively), crude fibre (5.08%, 7.20%, 5.90%, 4.22% and 5.10% respectively), crude protein (21.17%, 25.03%, 23.06%, 21.34% and 14.28% respectively), crude lipid (2.09%, 3.42%, 2.19%, 2.07% and 2.30 % respectively) and total carbohydrates (34.86% for sundried, 37.75% for microwave dried, 53.74% for oven dried and 73.16% for fried mushroom). Organic and dried matter were also analyzed. All five samples showed presence of sodium and potassium in varying amounts with sodium possessing the lowest values. The high protein, carbohydrate and fibre content obtained from all samples makes it suitable as a meal supplement. The preliminary phytochemical screening showed the occurrence of active compounds such as carbohydrates in all samples, alkaloids (in sun dried, microwave dried and oven dried samples), glycosides in all but fried sample and saponins in all but fried and fresh samples. Sun dried mushrooms contained the highest content of potassium, 1.00% while fresh mushroom contains the least potassium content, 0.97%. Deep fried, sun dried and microwave dried mushroom contained equal sodium content, 0.09% and fried mushroom contained the highest, 0.12%.
It therefore authenticates the use of Pleurotus pulmonarius as an excellent food supplement as well as exhibiting anti-carcinogenic, hypocholesterolaemic, hypoglycaemic and immunostimulant effects due to the phytochemicals present.
Funding Sources : Covenant University, Kilometer 10 Idi-iroko road, Ota, Ogun State, Nigeria.