877.812.1137

potassium metabisulfite

The Winemaker’s Think Tank: Vol 5 – Is Malocatic necessary in White Wines if it has not been inoculated?

Wine expert testing wine silhouette image

What’s the Winemaker’s Think Tank? 

Every Thursday we will post about a few frequently asked questions that our winemaker has answered. If you have a winemaking question you would like to have answered, please email us at support@juicegrape.com and we will try to get into next week’s post. Cheers! :)

Is Malocatic necessary in White Wines if it has not been inoculated?

When considering the stability of a white wine in preparation for bottling, sugar and microbial stability are of great importance. After fermentation, if MLF is not purposefully inoculated by the winemaker, the addition of Lysozyme may be considered as to retard any naturally present MLF bacteria from beginning to ferment. If the level of SO2 is kept up to is suggested level (contingent upon pH), the Lysozyme may not be needed as the SO2 will prevent the bacteria from fermenting. If the winemaker is trying to use a low amount of sulfites in their wine, I would suggest the use of Lysozyme to inhibit any bacterial growth.

Equally as important, is the use of sterile filtration. If the wine is processed through a sterile filter (.45µ), bacterial and yeast cells should be eliminated. This will physically prevent the bacterial spoilage of the wine. If the winemaker chooses to back sweeten the wine, this filtration will also help prevent any refermentation within the bottle. When it comes to back sweetening, I also always recommend chemical as well as physical sterilization of the wine to prevent fermentation and off aromas to develop within the bottle. Potassium sorbate may be used on any wine that has not gone through malolactic fermentation. If it is used on a wine that has undergone MLF, remaining MLF bacteria can begin to metabolize the sorbate, resulting in a strong geranium odor. In my experience, I typically add sorbate and sterile filter the wine, then bottle, without the addition of Lysozyme. I am meticulous about the level of SO2 remaining above the suggested amount , and I typically add an additional 10ppm before bottling to ensure prolonged sterility within the bottle.

While you certainly can conduct a chromatography test upon the wines to detect the presence of acid, both malic and lactic exist naturally within the grape, so the chromatography test will not be especially helpful when looking at a wine that has not gone through MLF. As long as you keep a vigilant watch upon your sulfur dioxide levels and pH, and use sorbate when sweetening, you should be fine.

We hope this information helps with your winemaking. If you have any follow up questions or winemaking questions in general, please email us at support@juicegrape.com. 

The Winemaker’s Think Tank: Vol 4 – What is the best way to sanitize my equipment?

Wine expert testing wine silhouette image

What’s the Winemaker’s Think Tank? 

Every Thursday we will post about a few frequently asked questions that our winemaker has answered. If you have a winemaking question you would like to have answered, please email us at support@juicegrape.com and we will try to get into next week’s post. Cheers! :)

What is the best way to sanitize my equipment?

It is important to differentiate between cleaning, sanitizing, and sterilizing. Cleaning is removing any dirt, grape debris, or build-up from your equipment. Sterilizing is the process via heat or chemicals of eliminating all micro-organisms, which is nearly impossible in a home winemaking environment. Sanitizing is the goal for home winemakers. Sanitizing is the removal of harmful micro-organisms from the winemaking equipment. This will give the winemaker the healthiest environment possible for their wine. One of the most chemically and cost effective ways to sanitize winemaking equipment is by using potassium metabisulfite. Potassium metabisulfite works best in an acidic environment. To create a strong sanitizing solution, mix 2 tbsp. of citric acid and 1 tbsp. of potassium metabisulfite with 5 gallons of warm water. Mix all of these in a 6 gallon pail. You can now use this solution to sanitize all of your equipment. Submerge or rinse all of the equipment in this solution. This solution will sanitize the equipment of any harmful bacteria that could spoil the wine. Any tool, vessel, or hose that touches the wine should be rinsed thoroughly with the solution to prohibit contamination.

Also, check out our Youtube Video where our Bootcamp Professor Frank Renalid weighs in on sanitation

 

We hope this information helps with your winemaking. If you have any follow up questions or winemaking questions in general, please email us at support@juicegrape.com.