Method for producing an extract of coffee beans
A method for producing an extract and/or a squeezed liquid, which includes: feeding a food to be extracted and/or squeezed into a crushing apparatus; adding a solvent into the crushing apparatus immediately after and/or while milling the food; extracting and/or squeezing a useful food component of the food into the solvent; and carrying out liquid-solid separation by removing the resulting extracted residue and/or squeezed residue with a continuous solid-liquid separation apparatus.
1. A method for producing an extract of coffee beans comprising
feeding roasted coffee beans into a twin-screw extruder from an inlet thereof, milling the coffee beans;
adding a solvent immediately after milling the coffee beans, followed by kneading said milled coffee beans to simultaneously extract an useful food component of the coffee beans into the solvent; and
subsequently carrying out continuous solid-liquid separation of a solid-liquid suspension extruded from an outlet of the twin-screw extruder with a continuous liquid-solid separation apparatus, thereby removing the resulting extracted residue to obtain the extract, wherein the operations from the kneading of the milled coffee beans within the twin-screw extruder to the liquid-solid separation with the continuous liquid-solid separation apparatus are carried out within a low temperature region with a solvent temperature of 2 to 30° C.
2. The method according to claim 1 , wherein the milling of the coffee beans is carried out such that the milled coffee beans has a mean particle size of 20 to 40 μm.
3. The method according to claim 1 , wherein the continuous solid-liquid separation apparatus is a decanter.
4. The method according to claim 1 , further comprising removing, with a centrifuge, a gustatory inhibiting substance contained in the extract.
5. The method according to claim 4 , wherein the centrifuge is a centrifugal separator for triphasic separation or a basket model vertical centrifuge.
6. The method according to claim 1 , further comprising absorbing and/or filtering the extracted residue remained in the extract from the extract.
7. An extract with no deterioration of flavor, which is obtained by the method according to claim 1 .