New filter aids for wine filtration

<p style="text-align: justify;"><strong>Aims</strong>: In a real concern to improve the quality and to reduce the pollution, the concept of « ecological filtration » based on the use of a regenerable filter aid is developed.</p><p style="text-align: justify;"><strong>Methods and results</strong>: Polyamide particles were tested as new filter aids for wine filtration. The particles were characterized with regard to water permeability and specific surface area. Filtration experiments were carried out at pilot scale under industrial operating conditions. Two test runs were performed using different suspensions and three grades of polyamide particles.</p><p style="text-align: justify;"><strong>Conclusions</strong>: In the first precoat filtration tests, the impact of polyamide particles on wine quality was determined by the chemical characteristics of the wine. Enological analyses showed that the precoat filtration of wine with polyamide particles did not affect wine quality and improved turbidity (97%), fouling index (80%) and the filtrate flux (compared to the usual precoat filtration with diatomites) . In the second test run, polyamide particle regeneration tests proved that these particles could be re-used as filter aids several times.</p><p style="text-align: justify;"><strong>Significance and impact of study</strong>: Polyamide particles used as filter aids in wine filtration were found to be very effective. Moreover, these particles are available in several sizes allowing their application at different stages of the wine-making process.</p>