Thermal processing can affect zinc availability in some edible mushrooms

• Rate of the release of zinc from edible mushrooms was determined by DP-ASV method.
• Release of zinc to artificial gastric juice was observed.
• Highest total content of zinc was released from Boletaceae species after thermal processing.
• Cooked mushrooms still remain an effective source of zinc.

The differential pulse anodic stripping voltammetry method was used for the determination of zinc released into artificial digestive juices from selected fruiting bodies of edible mushrooms (Boletus badius, Boletus edulis, Cantharellus cibarius, Leccinum scabrum, Pleurotus ostreatus, Suillus bovinus) before and after thermal processing which imitated food preparation. The total amount of zinc released from thermally-processed mushrooms ranged within 2.22–20.68 mg/100 g dry weight. The highest amount of zinc was determined in artificial digestive juices in thermally-processed fruiting bodies of B. badius and B. edulis. For C. cibarius fruiting bodies, thermal processing resulted in a slight increase in the release of zinc compared to the unprocessed fruiting bodies.In P. ostreatus species, the amount of zinc released into digestive juices before and after thermal processing was at almost the same order of magnitude. Thermal processing of fruiting bodies of B. badius, B. edulis and C. cibarius resulted in the release of significantly larger amounts of zinc into artificial digestive juices, which made them a very good source of zinc. In terms of fruiting bodies of S. bovinus and L. scabrum, an increase in temperature caused a partial reduction of zinc content; however, cooked mushrooms still remained an effective source of zinc.