Aseptically weigh 25 g sample into 500 ml tared sterile blender jar or Stomacher. Cut large samples into smaller pieces before blending. Add 225 ml alkaline peptone water (APW) to jar and
blend for 2 min at top speed. For oysters only (especially oysters freshly harvested from warm waters), prepare composite of 10-12 animals including shell liquor; blend to mix. Blend 50 g of this composite with
450 ml of APW. Pour 250 ml (g) of this mixture into another sterile container. Replicates for samples of oysters are incubated at different temperatures