Fermentation/Cellar – Microbial Control Agents
Lysozyme
Lysozyme is a naturally occurring enzyme isolated from egg whites which can be used in wine to control lactic acid bacteria (LAB). Lysozyme degrades the cell wall of gram-positive bacteria such as Oenococcus, Pediococcus, and Lactobacillus. Lysozyme is not effective against gram-negative bacteria like Acetobacter and has no activity against yeast.
Lysozyme's effectiveness depends not only on the type of bacteria, but also the number of cells present. Unlike sulfur dioxide, lysozyme is effective at higher pHs when LAB growth is favored. Lysozyme cannot completely replace sulfur dioxide, in part because it has no anti-oxidative effect. It can, however, be used to help reduce the amount of sulfur dioxide needed to achieve microbial stability over the life of both red and white wines. In general, red wines need higher doses of lysozyme due to loss of activity through polyphenol binding.
Lysozyme can be used in the following applications:
- Prevent growth of LAB in unsound grapes. Growth of LAB during primary fermentation can lead to sluggish or stuck fermentations. If grapes are unsound and have the potential to develop high levels of LAB, add lysozyme to discourage their growth at the juice stage.
| Recommended Dosage: |
| |
Reds and Whites |
100-200 ppm |
(10-20 g/hL) |
(0.38-0.75 g/gal) |
|
- Delay or prevent malolactic fermentation (MLF). Add lysozyme to hinder or block the onset of MLF at the juice stage. Some yeast strains have difficulty completing alcoholic fermentation when MLF occurs simultaneously. MLF may inhibit the primary fermentation due to the bacteria's competitive utilization of fermentable sugars, or due to the production of antagonistic by-products.
| Recommended Dosage: |
| |
Delay MLF in Reds and Whites |
100-200 ppm |
(10-20 g/hL) |
(0.38-0.75 g/gal) |
|
| |
Prevent MLF in Reds and Whites |
300-500 ppm |
(30-50 g/hL) |
(1.10-1.90 g/gal) |
|
- Stabilize LAB populations during sluggish or stuck alcoholic fermentations. Heterofermentative LAB can form excess amounts of VA, which may become toxic to the yeast and cause a sluggish or stuck fermentation. In addition, high VA wines may need to undergo costly treatment to remove excess VA. Treat the sluggish or stuck wine with lysozyme prior to reinoculation with yeast.
| Recommended Dosage: |
| |
Reds and Whites |
250-300 ppm |
(25-30 g/hL) |
(0.94-1.10 g/gal) |
|
- Inhibit the onset of MLF in the bottle. Add lysozyme to a finished wine that has partially completed MLF to inhibit the onset of MLF in the bottle.
| Recommended Dosage: |
| |
Whites |
300-350 ppm |
(30-35 g/hL) |
(1.10-1.33 g/gal) |
|
Important Note:
Lab trials must be conducted to determine the proper dosage of lysozyme for your wine.
Velcorin® - Microbial Control Agent
Velcorin® is the trade name for dimethyldicarbonate (DMDC), a microbial control agent produced by LANXESS®. Since 1988, Velcorin® has been used in the United States in wine, low-alcohol wine, and non-alcoholic wine as well as juice, juice sparklers, sports drinks, and ready-to-drink teas. Velcorin® is very effective at low dosages against a broad range of yeast, bacteria and molds. Unlike other chemical preservatives, Velcorin® is non-persistent and does not affect wine taste, bouquet or color. In addition, Velcorin® can remain active for several hours (depending on hydrolysis rate) thereby helping to eliminate contamination from other sources such as bottles, closures and filling equipment.
Velcorin® can be used in the following applications:
- To replace or decrease the amount of sorbate used in wines with residual sugar. Wines containing residual sugar are susceptible to refermentation in the bottle leading to haze, off-odors, off-flavors, and effervescence. Velcorin added to wine during bottling can help prevent refermentation.
- To decrease the amount of sulfur dioxide used in early-to-market wines. By lowering the amount of sulfur dioxide added, wines are palatable sooner and can be released earlier.
- To replace filtration in premium wines. Velcorin® can be used to prevent the outgrowth of spoilage yeast such as Brettanomyces. Brettanomyces is able to metabolize sugars including cellibiose from toasted barrels, leading to the evolution of 4-ethyl phenol and other undesirable sensory attributes. In this application, Velcorin® can be used before bottling to help control post bottling problems.
Conditions of Use:
Velcorin® must be used with an approved dosing system.
Scott Laboratories can only sell Velcorin to those using a LANXESS® approved dosing machine. Velcorin® is a chemical and must be handled with respect. Therefore, all Velcorin® handlers must undergo annual safety training (provided at no charge by Scott Laboratories). The current cost of a Velcorin® dosing machine is about $50,000. For more information on Velcorin® and dosing machines, please contact Jessica Just at Scott Laboratories.
Mobile Velcorin Services Are Now Available!
Five mobile Velcorin service providers with approved dosing machines are now available and listed below.
Bottlemeister
979 Osos Street C1
San Luis Obispo, CA 93401
Phone: 805-541-8404
Fax: 805-541-8412
e-mail: velcorin@thebottlemeister.com
www.thebottlemeister.com
Contact: Tom Nulman
Castoro Cellars
1315 N. Bethel Road
Templeton, CA 93465
Phone: 805-467-2002
e-mail: niels@castorobottling.com
www.castorocellars.com
Contact: Niels Udsen
Cru Northwest
3995 Deepwood Lane NW
Salem, OR 97304
Phone: 503-689-6860
e-mail: mike@crunorthwest.com
www.crunorthwest.com
Contact: Mike Mitchell
Electrotec
Central Coast Phone: 805-227-6686
North Coast Phone: 707-280-8219
e-mail: andre@electrotecservice.com
www.electrotecservice.com
Contact: Andre Austin
Mobile Wine Services, LLC
567 E Spring Street
Napa, CA 94559
Phone: 707-227-7426
e-mail: chris@mobilewineservices.com
Contact: Christian Troussieux
Vinpure
5300 Mountain Home Ranch Road
Calistoga, CA 94515
Phone: 707-942-2740
Fax: 707-942-2744
e-mail: info@vinpure.com
Contact: Lyall Fahden, Karen Fahden
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