| 摘要 |
PURPOSE:To obtain a method of extracting and preparing coffee, capable of providing mellow coffee having body, slight astringency, hardly causing heartburn and a structure therefor. CONSTITUTION:Coffee is passed through a route arranging or comprising positive and negative interfacial potential layers to extract and prepare coffee. The structure for extracting and preparing coffee is equipped with a filter 1 having water permeability and a slightly water permeable member 2 at close range at the outflow side of the filter. Coffee C is permeated from the inflow side to the outflow side and the coffee passed through the coffee is run between the filter and the slightly water permeable member. The filter l and the slightly water permeable member 2 form an interfacial potential layer of three layers wherein interfacial potentials of the adjoining layers invert positive and negative. Tannins in the passing coffee are controlled by the layers. Preferably an auxiliary containing a hydrophilic polymer compound having swelling properties, slight solubility and affinity for tannins is dispersed in coffee. |
