Cross-Flow Filtration

Cross-Flow Filtration – used right before we bottle the wine.

Wine is run over a thin organic membrane. The liquid parts of the wine pass through the membrane, while the particles are pushed across. Wine passed through the membrane is bottled.

We don’t always filter. But when we do, we prefer to use a Padovan 4 Chamber Cross-Flow Filtration System.


Wine is ever-changing, even in the bottle. There is always a chance the wine can spoil. Any bacteria remaining in the wine after bottling increases the risk of spoilage. Cross-flow filtration not only removes remaining yeast particles that cloud the wine, but it also eliminates all presence of bacteria. We prefer our wine to be bacteria-free.


When the opportunity presents itself. For the 2019 vintage, we have two wines that are unfiltered. Our 2019 Quail Hill Chardonnay, and the 2019 Bacigalupi Pinot Noir.

Both wines went through full Malolactic Fermentation (we will talk more about this in a future post). This secondary fermentation gets rid of any unwanted bacteria.

We are extremely excited about all the changes at Cast. This is the first vintage we have used a cross-filtration system. Imagine feeding the wine through a giant sponge several times. Now imagine the wine flowing across the surface of the sponge. Both get the job done. The latter is much gentler on the wine, works more efficiently, and wastes less wine.

Our primary objective is the safety of our guests and our staff, while providing a relaxed and enjoyable experience. Our abundant outdoor spaces prove ideal for safe distancing as we continue to create memorable experiences with you!

Outdoor tastings are by reservation, 7 days a week from 10am-5pm (last reservation at 3:30pm).

 We follow procedures established by Sonoma County and the State of California.

Please Reserve online by clicking on the “Visit” tab on our website. Several options are available for members and guests. Our maximum group size is six people per reservation. We ask that you review our Updated Visitation Policy prior to making your reservation.

Questions or need help placing an order? Call (707) 431-1225 or email us at

Thank you and we look forward to hosting you!