MUST AND JUICE CLARIFICATION: TANK THROUGHPUT
The Sediment Interface Detector from Raven: A new tool for winemakers.
MUST CLARIFICATION / DeBOURBAGE
When is the optimum time to rack the must?
You have a brief window of time during juice clarification to produce a must that will blossom in the fermentation tank. A noted winemaker calls this “goldilocks” juice. Not too heavy, not too thin, but just the right amount of goodies for a perfect balance of esters and alcohol.
Winemakers throughout the world say must clarification is the most important stage after harvest for white wine production. Problems at this stage create challenges later.
The Sediment Interface Detector (SID) puts process control in your hands. Track how fast the wine must is settling and predict if a tank will need assistance to avoid a problem.
TRUST BUT VERIFY
Spontaneous juice setting is preferred. And the SID is a useful tool to confirm that the grape solids are precipitating naturally and as expected.
Bentonite, or potassium caseinate is commonly used when a must clarification tank is “stuck” and not progressing at a satisfactory rate. Although wine fining agents clarify the supernate, they also increase the sediment layers and the amount of juice trapped at the bottom. Verify fining adjustments on the spot with the SID to minimize waste and labor.
The SID informs the winemaker how much sediment is in the bottom and logically how much juice is ready to rack. The cellar crew becomes more efficient at routing wine hose to the appropriate receiving tanks. Stop schlepping hose all over the cellar.
With tons of fresh wine grapes waiting, clarification tank throughput is critical. Avoid “bottlenecks” in the white wine must clarification stage of production and keep the fruit flowing thru cold settling to wine fermentation. The SID is a process control tool that wineries will use throughout the day to help keep production on schedule.
Racking white must too soon risks bringing excess suspended solids to the fermentation tank which could lead to excess fusel alcohol production and impaired fruitiness. Excess suspended solids in must are known to produce hydrogen sulfide which causes off-odors.
Delayed racking may bring on fermentation in the must clarification tank from wild or winery yeast. In addition, removal of too much suspended solid matter may slow down alcoholic and malolactic fermentation.