Winemaking may be an ancient art, but modern innovations have vastly improved methods and outcomes. Here are a few scientific and technological developments that can drastically enhance a finished wine. For more detail, seek the advice and assistance of a specialty lab in your area.
Fining. Fining agents can be used on wine to deal with a variety of issues, but it’s important that treatments are done at the proper time. Fining can help enhance a wine’s clarity as well as improve filterability. In general, fining is recommended to take place six to nine weeks prior to bottling.
Filtration. The cleaner your wine is before filtration, the more cost effective that filtration will be. Limited contact and settling time for fining agents may result in incomplete effect and higher clogging during filtration. More clogging leads to higher filtration and labor costs.
Finishing and fine-tuning wines. The best time to make final adjustments to a wine is six to nine weeks prior to bottling. This can include blending as well as tannin additions for fine tuning of aroma, fruit, or mouthfeel.
Heat and cold stabilization, prebottling. Once a wine is blended, clarified, and/or adjusted, it is often protein stabilized with bentonite and tartrate stabilized by one of several methods (for more information on these methods, please contact us). It’s recommended to heat (protein) stabilize prior to cold (tartrate) stabilization, as bentonite additions may alter tartrate stability. It’s important to use a bentonite that has good protein removal capacity; sodium-based bentonites have better protein removal capacity than calcium-based bentonites, while calcium-based bentonites compact lees compact lees better. Sometimes, a blend of the two can produce the best results. Bench trials for stability and compaction can save time and money.
Bentonite is an effective adsorption tool that’s indiscriminate between desired and undesired proteins. Strategies can be employed to mitigate large bentonite adds. Small additions (2g/hL) of FT Blanc help form tannin protein complexes, which reduce instability. Colloidal silica, such as Gelocolle, works on high molecular weight proteins while bentonite works on low molecular weight proteins. Colloidal silica can be used to reduce total bentonite requirements (bentonite should be added first then colloidal silica). Bench trials should be run to determine correct additions.
Performing a rough filtration prior to heat stabilization, whether the wine was fined or not, will help create a clearer product to stabilize. For rough filtration, a 3-10 micron range depth filter media is recommended.
Colloidal stabilization. Gum arabic products act as colloidal stabilizers by using electrical charge attraction and repulsion. Gum arabic is only effective in conditions of very low to no tartrate instability. They’re often more effective at color stabilization by complexing with tannins and polyphenols.
Gum arabic should be added 24 to 72 hours prior to bottling. Always check filterability after its addition. Gum arabic shouldn’t be added to wine immediately prior to filtration, as it may clog membrane filters. Adding right before a crossflow filtration can also place undue pressure on the elements and cause long-term damage.
Bottled wine. Stabilizing your wine before bottling reduces the chance of haze or precipitation in the bottle. Wines that drop tartrates are subject to colloidal precipitation. This can leave bottled wine prone to oxidation and microbial problems if a final filtration with a .45 micron membrane filter is not performed.
For more than 80 years, Scott Laboratories has been meeting the needs of the beverage industry with innovative solutions and products including fermentation and filtration goods, winemaking equipment, and cork and packaging products. With local facilities in Petaluma and Healdsburg, Calif., Scott Labs is poised to assist in all beverage needs.