Beverage preparation from a substance compacted into a cake

In a process for preparation of a beverage wherein an extraction fluid is introduced into a sachet which contains a substance which is suitable for preparation of a beverage for obtaining a beverage, the improvements comprising:

• positioning a sachet which contains a compacted powder substance cake for preparation of a beverage, wherein the sachet comprises two sheets impermeable to oxygen and water vapor and wherein the cake comprises two cake surfaces which extend to a peripheral cake edge and wherein the two cake surfaces have a convex shape, adjacent a surface of a device for extracting a substance under pressure so that one of the two sheets is adjacent the extraction device surface and wherein the extraction device surface comprises portions so that upon extraction of the substance under pressure, first, the sheet adjacent the extraction device surface deforms and so that, subsequently, local breakages form in the deformed sheet for providing sheet openings for flow of beverage through the sheet openings and wherein upon the positioning, the cake is positioned between the two sheets and the two sheets extend to peripheral sheet edges which extend beyond the peripheral cake edge and are sealed together to form a sealed edge which circumscribes the sheets so that the cake is enclosed between the sheets and so that the two sheets circumscribed by the sealed edge are substantially symmetrical so that the sealed edge defines a plane through the sachet and wherein the cake and sachet are configured so that the cake has a volume so that there is free space between the cake and at least one sheet and so that the free space is in an amount of less than 20% of a sachet internal volume between the sheet portions circumscribed by the sealed edge, and then, perforating one sachet sheet with at least one perforating member to provide at least one opening for introducing an extraction fluid into the sachet to the cake for extracting the cake substance under pressure for preparing the beverage;
• injecting an extraction fluid under pressure into the perforated sachet and to the cake substance via the at least one opening so that the cake substance is extracted under pressure for preparing the beverage and so that first, the one sheet positioned against the extraction device surface deforms and so that subsequently, localized breakages form in the deformed sheet to provide sheet openings for flow of the beverage from the sachet to obtain a beverage flow from the sachet;
• and
• obtaining the beverage flow from the sachet.