How to do paper chromatography
Paper chroma-whata??
Paper chromatography: the way that home winemakers (and some commercial winemakers) check to see if their wines have completed malolactic fermentation or if they are still in the process of it. This is the time of year that winemakers are staying up on at what point their wine is at in the process of malolactic fermentation, because it will dictate when they can add potassium metabisulfite for the first time to their finished wine.
Why is it important?
Some wines should go through MLF for stylistic and stability reasons, whereas others should not.
How do I do it?
You’ll need to get a paper chromatography kit. This includes 3 acid standards (malic, lactic, tartaric), the solvent solution, chromatography paper, capillary tubes, and a plastic jar.
How accurate is it?
That’s the thing – it’s more qualitative than quantitative. Maybe it will show that there is still malic acid present, but that doesn’t mean it tells you how much is present, how long it’s been at this point, or if it’s even still decreasing anymore. It is qualitative in the sense that it shows: yes, acid X is present, or no, acid X is not present. If you’re searching for a more exact number or reference point you can send your samples in to a lab – if you’re looking to get an overall picture of whether or not your wine has any malic acid or lactic acid present, then using paper chromatography is the way to go.
What does this stuff look like?
The yellow circle indicates the presence of certain acids
How do I do it?
- Collect your wine samples
- Draw a line 1-2 inches from the bottom of the paper using a pencil (pen will not work)
- Mark with an X or dot where you will place the samples.
- Use capillary tubes (one for each sample – don’t mix them up) to draw up a very small sample of the the standards (malic, lactic, and tartaric) and then the wine samples and drop a very small amount of the liquid onto the paper. You will notice it will spread out once it hits the paper so be sure not to drop too much liquid. Less is more here.
- Let the dots dry and repeat 3 times. This will make it easier to read down the road.
- Roll the paper up and staple either side without the paper overlapping onto itself.
- Pour a small amount of paper chromatography solvent solution into the bottom of the plastic jar. Be careful to not inhale this. Place the stapled paper, sample side touching the solution, into the jar. Screw the lid on and let sit for ~8 hours, or enough time for the solvent to reach from the bottom to the top of the paper.
- Take the paper out (carefully) and let it air dry until the entire sheet turns blue and yellow dots are clearly visible.
- Match up where you see specific acid dots with the wine samples and you can detect if malic and/or lactic acid is present in each sample.
Capillary tubes are used as the method of dabbing wine samples onto the sheet of paper.
Helpful hints
You will likely need to run this test at least a couple of times to see the decline in MLB and confirm its completion
Be sure not to add any potassium metabisulfite to your wine until MLF has completely finished!
Use space heaters or a warm room for wines undergoing MLF to help speed the process along
Collect your test samples
Musto’s Wine Analysis Services
If you’ve ever found yourself wondering…
- How do I get accurate numbers on my wine samples?
- Can I trust the readings I’m getting?
- How do I even do this test?!
…fear not! Musto Wine Grape Company can happily assist you with all of your wine analysis needs.
Samples to be tested – a truly beautiful sight!
What analyses do we offer?
- Brix, pH, TA
- Free and/or total SO2
- Alcohol
- MLF
- YAN
- Sensory analysis
Why is analysis important?
- Knowing the Brix, pH, and TA of your juice sample is the most important first step pre-fermentation. Depending on these numbers you may need to acidulate (add acid) or ameliorate (add water) to your must or juice before initiating fermentation.
- SO2 levels will indicate how well protected your wine is. You may need to add more or less depending upon the reading.
- Alcohol % (ABV) is an important number to confirm, especially if looking to confirm the final number for a wine label.
- The presence of malolactic bacteria will indicate whether or not MLF has completed in your wine.
- YAN numbers will tell you the amount of yeast assimilable nitrogen levels will help you decide how much nitrogen/nutrients you may want to add throughout the alcoholic fermentation.
- Sensory analysis entails our highly knowledgeable and skilled staff conducting a taste test on your samples. This is especially helpful if you are looking to see how to improve upon your current wine, or how to sharpen your winemaking skills for future vintages.
pH and TA are important numbers to know as they will affect the entire winemaking process from start to finish
Interested in getting your wines analyzed at our lab?
Great! There’s one of two ways to get your samples to us:
- Drop by to say hello and give them to us directly. You can fill out a lab analysis form from our website to bring in with you.
- Send them in with the above lab analysis form. Be sure to include all of your contact information!
Acid titration
Any other questions? Give us a call at 860-278-7703. We’re always happy to help you make your wine the best it can be!
Winemaker Lab Skills Class – October 9th
Musto’s Winemaker Lab Skills Class will be held on Wednesday October 9th at 7:00PM.
Want clarification on TA, pH, and Adjusting Your Wine?
Then this is the class for you!
Professor Frank Renaldi will go over the following lab skills every winemaker needs. It can be difficult to feel comfortable testing your wine. However, Frank has some easy tricks and tips of how to test and adjust your wine.
Class Outline:
- Equipment & Supplies
- Volume Measurements
- Sugar, Content, & Adjustments
- Acidity, Content, & Adjustments
- pH
- Sulfites, Need, & Adjustments
- Blending
- MLF
- Sugar Addition
Sign up today and start sharpening your Winemaker Lab Skills!
Sign up via the website HERE or give us a call at 877-812-1137 to sign up over the phone. We look forward to seeing you in class. Cheers!
The Winemaker’s Think Tank: Vol 18 – Tips for Racking Your Wine
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! 🙂
The Joys of Racking Wine….
Racking your wine is a necessary evil. We know it can be tedious, but it the end it is so worth it.
Things to keep in mind when racking:
• Cleanliness: We cannot express this enough. The cleaner your cellar, the less risk you have of spoilage, the better your wine will be. Aka SANITIZE EVERYTHING!! (however if doing MLF rinse with hot water as not to kill the ML bacteria) Use a solution of potassium metabisulfite dissolved in warm water. Add 2 tbsp to a 5 gallon bucket of water. Make sure that everything that will touch your wine (siphon, hosing, carboys, stirring rods) are all rinsed with this solution. Do not rinse it off with water, just shake off any excess droplets.
• Primary Racking: Rack after your primary alcoholic fermentation is complete. This protects your wine from any initial microbial fermentation issues. Getting the new wine off of the dead yeast cells in important for the health of your wine to prevent off aromas.
• Secondary Racking: Rack after the Malo-Lactic fermentation has finished. At the second racking you will want to rack your wine into an aging vessel. Whether that is a stainless steel tank or an oak barrel. Don’t forget to sulfite, unless you are doing MLF.
• Third and/or Fourth Racking is used more for clarification purposes. Solids and fining agents (if used) will fall out of suspension and form a layer on the bottom of your aging vessel. Racking every 2-3 months, will consistently clarify your wine.
• Using a pump makes life so much easier. You can pretty much sit back and relax with a glass of wine while your juice is being transferred. If you don’t have a pump the best way to rack is by using a siphon and the gravity method. Put the primary vessel up some place high (a table) and rack into your new vessel on a lower surface (floor).
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 5 – Is Malocatic necessary in White Wines if it has not been inoculated?
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.
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