Capsule for food or beverage preparation having a displaceable membrane for engagement with opening means

Capsule for food or beverage preparation, the capsule comprising:

• a hollow body and an injection wall which is impermeable to liquids and to gases and which is attached to the body and adapted to be punctured for fluid injection into the capsule,
• a chamber formed inside the body containing an ingredient for preparing food or beverage by dissolution with the fluid under pressure or extraction by the fluid under a preparation pressure,
• a membrane disposed at a bottom end of the chamber, for retaining internal pressure in the chamber,
• an opening member located outside the chamber in the vicinity of the membrane, the opening member being configured to open the membrane when the membrane is pressed against the opening member under an opening pressure, and
• the membrane is attached to the body of the capsule by an adhesive seal which, when a release pressure, less than the opening pressure, is established inside the chamber and applied to at least part of the surface of the membrane, is configured to allow the membrane to be displaced relatively to the body and to engage against the opening member while maintaining an attachment between the body and the membrane.