Method for delivering a coffee extract from a capsule

A method for delivering a coffee extract from a capsule containing ground coffee within a flow time of less than 35 seconds per 110 mL extract by injection of water under pressure within the capsule, which method comprises:

• providing a ground coffee containing capsule for extraction in a coffee extraction device where water is injected into the capsule under pressure to deliver the coffee extract;
• providing the capsule with a delivery membrane having a puncture resistance of between 1.1 and 3.5 mJ;
• providing coffee ground using a grinder comprising a fine grinding section that includes at least one pair of radially corrugated rolls to provide ground coffee having an average particle size of less than 350 microns, and a controlled percentage of fines (F) depending on the average particle size (D4,3) within the following limits:
• F is between 12 and 16% when D4,3 is measured from 300 to 349 microns, and
• F is between 14 and 18% when D4,3 is measured from 250 to 299 microns;
• filling the capsule with a bed of the ground coffee wherein the delivery membrane initially retains the ground coffee in the capsule;
• and
• delivering a coffee beverage after the water pressure injected into the capsule reaches a value higher than 11 bar by releasing the coffee beverage through the delivery membrane of the capsule with engaging means engaging in or against the membrane to provide an exit for the coffee beverage, thus delivering a coffee beverage having a total solids of between 1 and 1.9% wt. and an extraction yield of between 15 and 30%.