As an expert sommelier and brewer, I have extensive experience in filtering lees from wine and I am happy to share my knowledge with you. There are various methods used in the industry, but I will focus on the traditional methods involving diatomaceous earth (DE) filtration systems like rotary vacuum drum filters (RVDF) and chamber press filters.
1. Rotary Vacuum Drum Filters (RVDF):
– RVDF is a popular method for filtering lees and is commonly used in wineries.
– This filtration system consists of a rotating drum covered with a filter medium, typically DE.
– The lees are pumped into the drum, and a vacuum is applied to the inside of the drum, which helps draw the liquid through the filter medium, leaving behind the lees.
– The filtered wine is collected and can be further processed or bottled.
2. Chamber Press Filters:
– Chamber press filters are another commonly used method for lees filtration.
– This system involves a series of chambers with filter plates that are pressed together.
– The lees are pumped into the chambers, and pressure is applied to force the liquid through the filter plates, leaving behind the lees.
– The filtered wine is collected and can be further processed or bottled.
Both RVDF and chamber press filters have their advantages and disadvantages. RVDF is known for its continuous operation and faster filtration rate, while chamber press filters offer higher pressure for better lees compaction. The choice between the two depends on the specific requirements and preferences of the winery.
In my personal experience, I have found that using DE as the filter medium provides excellent results in terms of clarity and flavor retention. DE is a natural substance composed of fossilized remains of diatoms, which are tiny aquatic organisms. It has a high porosity, allowing for efficient filtration while retaining desirable flavors and aromas.
When using DE filtration, it is important to prepare a slurry by mixing DE with water before adding it to the filtration system. This helps ensure even distribution of the DE and prevents clogging of the filter medium.
It's worth mentioning that while DE filtration is effective in removing solids and impurities, it may also remove some desirable compounds that contribute to the wine's texture and mouthfeel. Therefore, winemakers need to find a balance between filtration and preserving the wine's character.
To summarize, filtering lees from wine can be done using diatomaceous earth filtration systems like rotary vacuum drum filters or chamber press filters. These methods offer efficient removal of solids while retaining the desired flavors and aromas. However, winemakers should be mindful of potential flavor loss and find the right balance between filtration and preserving the wine's unique characteristics.