Phenolics and antioxidant activity of a ready‐to‐eat snack food prepared from the edible mushroom (Agaricus bisporous)

Purpose The purpose of this paper is to evaluate the total polyphenolics, flavonoids and antioxidant properties of a ready to‐eat snack food prepared from Agaricus bisporous. A comparison of these properties with the raw, unprocessed mushroom was also carried out. Design/methodology/approach Extracts of raw and snack mushrooms (osmotically dehydrated, dried and spiced and following sensorial analysis) were analyzed for antioxidant activities using DPPH and ABTS radical scavenging methods. Flavonoids were determined by the method of Jia et al. Total polyphenolics (free and bound) were determined by the Folin‐Ciocalteu method; reducing power and hemolysis inhibition of the extracts were determined by the methods of Oyaizu and Zhang et al. Findings Scavenging activity of free extracts of raw and dry snack mushrooms on DPPH radical were 76 per cent and 72 per cent respectively. The ABTS radical scavenging activity of the free extracts of raw sample was 2.76 mg ascorbic acid equivalents/100 g and 2.67 mg ascorbic acid equivalents/100 g snack mushroom. Both free and bound polyphenolic contents in mushroom snacks were slightly higher than raw mushrooms, total flavonoids levels decreased marginally in snack mushrooms. Hemolysis inhibition was decreased (marginally) in free extract of snack mushroom as compared to raw mushroom whereas total reducing power of snack mushroom extract increased significantly. The antioxidant status was unaffected following storage of the snack at ambient temperature for up‐to 15 days. Research limitations/implications Mushrooms snacks may serve as a good alternative for currently existing snack foods since they retain a significant amount of polyphenolics and antioxidants; mixed with other commonly used snack foods it may provide beneficial health effects to the consumers economically. Practical implications A simple, economical process for preparation of Agaricus bisporous snack using sequential application of osmotic dehydration and drying was optimized; the snack mushrooms possessed functional properties comparable to raw, unprocessed mushrooms. Originality/value This paper reports for the first time a simple, economical process for preparation of functional snack food from mushrooms.