Fermented Swiss Brown Mushrooms

• 8 medium-size swiss brown mushrooms
• 250 ml (9 fl oz) still mineral water

Peel the mushrooms and cut the stems level with the base of the mushroom cap. Cut two 5 mm (¼ inch) thick slices off the mushroom from the base so that the cross-section of the mushroom includes both white mushroom flesh and brown gills. Place the 16 slices of mushroom in a cryovac bag in a single layer. Combine the mineral water and salt to form a brine then pour into the bag and seal it with