Best Practices for Juice Clarification via Settling
Last updated: 9/2022
Applies to: Winemakers using fining agents for clarification in the juice phase.
THE IMPORTANCE OF JUICE CLARIFICATION
Clarification is commonly done prior to fermentation via static settling to decrease the level of solids in the juice. Benefits of solids reduction (clarification) include:
- Fresher, fruitier wines
- Reduced sulfur off-odors
- Better color as enzymes responsible for oxidation have been removed
- Reduction in acetic acid producing native microflora
Enzymes and fining agents are used in the juice phase to facilitate settling, which may or may not happen on its own. Enzymes are added to remove pectin, fining agents are added to bind and remove solids and other undesired compounds. Scott Laboratories recommends the following order of operations:
- Add Enzymes
- Add Fining Agent(s)
- Allow Time to Settle
Enzymes break down pectin in juice and wine. Pectin traps solids and other undesirable compounds in suspension and slows or prevents settling. Pectin will also slow or prevent fining agents from settling.
It is difficult to know if a wine has a problematic level of pectin without testing, and bench top trials can be unreliable. Typically, pectin problems are discovered when a fining agent won’t settle out. At this point, it may be too late to use enzymes as some fining agents like bentonite can deactivate enzymes. Proactive use of enzymes is an inexpensive fix to avoid this issue.
PRO TIP: Enzymes used for settling can be added at the press pan to facilitate mixing and to give them time to work before the juice is chilled in tank. Enzymes do not work as efficiently at cooler temperatures.
ADD FINING AGENT(S)
Fining agents bind with solids and other undesirable compounds, forming larger molecules called floccules, which fall out of solution more quickly than unbound solids.
When adding a fining agent it is important to properly rehydrate the product, as well as adequately disperse it into the wine. Pumping using a venturi is an efficient way to disperse agents prior to fermentation. Closed circulation after addition is recommended.
PRO TIP: It is critical to give time for enzymes to work before bentonite-based fining agents are added, as they will deactivate enzymes. The amount of time needed between additions depends on tank temperature and enzyme dosage.
ALLOW TIME TO SETTLE
The floccules created by the fining agent will settle to the bottom of the tank over time. Temperature is the main driver of settling rate, and extreme cold temperatures (close to freezing) can inhibit settling and will also inhibit most enzyme activity.
Choosing Products for Juice Clarification
For easy to clarify juices
|SCOTTZYME® PEC5L or SCOTTZYME® KS|
For difficult to clarify or cold juice (<50°F)
|RAPIDASE® CLEAR EXTREME|
|RECOMMENDED FINING AGENT|
or QI'UP XC or INOCOLLE
|Clarification AND Treatment/Prevention of Oxidative Damage||NO[OX] or POLYCACEL or FRESHPROTECT|
|Clarification AND Treatment of Off-Odors||GRANUCOL® GE or BENTOLACT S|
Note: if making a rosé, or needing to adjust color, try GRANUCOL® FA or POLYCEL which may be used in conjunction with other fining agents.