Diatomaceous Earth’s Role in Wine Filtration

Cheers to This Year’s Wine Crush


diatomaceous earth for wine filtration

Great news for wine enthusiasts! The 2019 wine crush season is upon us. Grapes are ripening a few weeks later than normal after a cool, wet spring that caused some concern. But, mother nature pulled through, and early reports suggest that crops are in good shape, even if the harvest is pushed back. In honor of this year’s wine crush, we’re going to take a look at wine filtration and why diatomaceous earth is a top choice.

Wine Filtration

Winemakers and consumers can agree wine is best when free of questionable particles floating around in the bottle or cup, especially when those particles are often gelatinous or deformable materials, including yeast, bacterial cells, and many colloids. Yuck! Common filtration choices for wine are:

  • Cross-flow Microfiltration: Feed flow travels parallel to the filter instead of through. The pressure is the key factor.
  • Centrifugation: This type of filtration works at a high speed and a high flow rate with the aid of gravity, but it only removes a portion of dense particles.
  • Diatomaceous Earth: This mineral is used as a mechanical filter aid for filter presses and rotary vacuums.

Why Diatomaceous Earth is Best for Wine Filtration

Diatomaceous earth is the naturally occurring fossilized remains of diatoms—single-celled aquatic algae. It is a near-pure sedimentary deposit consisting almost entirely of silica. If viewed under a microscope, you would see diatoms have a wide variety of shapes and a honeycomb-like structure, making it an ideal filtration medium. Plus, the packing of the small diatoms is irregular and creates a complex matrix with high porosity. This allows the filter media to both remove very small particles and extend the flow rate of the material being filtered.

The pores within and between the cell walls of diatomaceous earth are so small, they trap bacteria, clay particles, some viruses, and other suspended solids from liquids. This leaves the wine cleaner and with drastically reduced solids and contaminant levels. Diatomaceous earth filters can be used alone or as the second step in the filtering process. Screens or pre-filters can be employed first to eliminate larger particles before reaching the diatomaceous earth filter.

And equally importantly, diatomaceous earth does not impart any odor or foreign taste to the wine.

Operation notes: 

  • When using DE with a filter press, the precoat cake performs the essential filtration (not the filter cloth), so filter cloth specifications must be matched to the performance of the filter aid grade
  • A uniform precoat cake thickness of 1/16″ to 1/8″ requires 10-20 pounds of diatomaceous earth filter aid for every 100’sq of filtration area
  • Fill the filter vessel with “clean” liquor before introducing the precoat slurry to help ensure uniform cake formation

Achieve Brilliant Clarity with Dicalite Management Group‘s Diatomaceous Earth for Wine Filtration.

Polishing filtration is an integral part of the winemaking craft. Leading vintners everywhere rely on Dicalite filter aids. Call us today at 866-728-3303 to speak with one of our knowledgable reps and to request your free sample.