Concentration of red wine by nanofiltration

Red wine contains many compounds which have a beneficial effect on human health. The aims of this study were to concentrate the valuable components of wine by nanofiltration, to describe the mathematical model of the permeate flux and to estimate the cost of the process. Laboratory-size equipment with a nanofiltration membrane was used for the concentration. The experiments were carried out at constant pressure, different temperatures and different recycle flow rates. The concentration of compounds was analyzed in the permeate and retentate including total acid, total extract, alcohol, sugar, free sulphurous acid, total sulphurous acid, sugarless extract content and volatile acid content. A mathematical modelling and cost analysis of the process were also performed.

(11) The specific investment cost realated to 1 m3 of processed red wine is: (12) During concentration, the alcohol and the water passed through the pores of a NF membrane. Thus the permeate can be utilized as a raw material in the alcohol industry. The retentate is the final product with a similar alcoholic content than that of the original wine, with about two times a higher concentration of valuable components. If water is added to the retentate, the product will be similar to the wine but with a decreased alcohol content.