Nutraceuticals and Antioxidant Activity of Prepared for Consumption Commercial Mushrooms Agaricus bisporus and Pleurotus ostreatus

Agaricus bisporus and Pleurotus ostreatus mushrooms (raw or blanched) were prepared for consumption by braising with 10% rapeseed oil. Fresh mushrooms and mushroom products directly after preparation and storage were analyzed. Fresh mushrooms were characterized by typical proximate composition, content of nutraceuticals and antioxidant activity. One hundred grams fresh weight of ready-made mushrooms fulfilled 2–9%, 10–34%, 7–12% and 1–8% of Recommended Dietary Allowances for adults set by Food and Agriculture Organization/World Health Organization of vitamin B1, B2, B3 and B6, respectively. One hundred grams dry weight of ready-made mushrooms contained 151–300 mg of catechin equivalents of total polyphenols, 35–98 mg of catechin equivalents of total flavonoids, 2.1–5.5 mg vitamin of C, 0.548–1.004 mg of β-carotene, 0.336–0.450 mg of lycopene and 40.46–55.16 mg sum of tocopherols and were characterized by high antioxidant activity in 2,2-azino-bis[3-ethylbenzthiazoline-6-sulphonic acid] (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Ferric Reducing/Antioxidant Power (FRAP) assay. Blanching resulted in lower levels of nutraceuticals and lower values of antioxidant activity. Storage of mushrooms prepared for consumption led to decreases in the amount of several nutraceuticals and to the growth of microorganisms. Practical Applications Commercial mushrooms such as Agaricus bisporus and Pleurotus ostreatus are very popular foods. In Europe, almost 2 kg per person of those mushrooms are consumed every year. As fresh mushrooms are stodgy, they are rarely consumed raw; usually, they are cooked, braised, fried or preserved prior to consumption. The chemical composition and antioxidant properties of fresh mushrooms are widely described in the literature; however, information pertaining to the vitamin content in mushrooms (estimated by high-performance liquid chromatography techniques) and characteristic of processed mushrooms is lacking. The aim of this study was to evaluate nutraceutical and antioxidant properties of commercial mushrooms after preparation for consumption by braising. This research provides information as to how braising and storage after treatment affects vitamins, antioxidants and antioxidant activity of commercial mushrooms. It also allows estimating the storage period for mushroom culinary products basing on microbiological evaluation.