Malolactic Chromatography Test
Can you handle more lab tests? About a week ago I showed you how we tested the juice for the sugar. This week we are testing wine! One test run on most red wines is a chromatography test. To explain what this test will tell us, I first need to tell you a bit about the wine chemistry. Don’t worry, it won’t be tough and there are no pop-quizes!
When wine ferments, one of the acids left in the wine is called malic acid. Malic acid is nice for fresh fruity wines or those with some sugar in them, but it’s a fairly tart acid. Red wines are often dry, and too much malic acid can stand out and be, well, too tart! So we put the reds through a process called ‘malolactic fermentation’ where a special bacteria called ‘malolactic bacteria’ (how’s that for some cleaver naming!) eats the malic acid in the wine, leaving behind lactic acid.
You might be wondering why this is a good thing. After all, malic acid…lactic acid…they are both acids, so wouldn’t they both be tart? And yes, while they are both acids, they will each leave a very different sensation in your mouth. Lacitic acid doesn’t have that harsh tart edge to it that the malic acid has. In other words, the lactic acid feels softer in your mouth. So for dry wines, the lactic acid is much easier on your taste buds.
The chromatography test will show us whether the malolactic (abbreviated ML) fermentation is finished and whether all the malic acid is gone from the wine. Several dots of wine are placed at the bottom of a sheet of absorbent paper. Then the paper is rolled into a cylinder and placed in a jar with an inch or so of orange chromatography liquid chemical-y stuff (that’s my name for it, since I’ve learned from the malolactic-naming people). Without getting to technical, basically as the liquid migrates up the paper, it carries the acids in the wine on up with it. Each acid is left in different spots and will keep the paper from turning color. Depending on where you see color, you’ll know if the ML fermentation is finished or not. This might make more sense at the end when I show you a finished test!
Clyde is testing three wines on this sheet of paper. The dot on left is a 2012 Norton, which we know has already finished with it’s malolactic fermentation. This will be our control, so we can compare the results on the other two wines. The dot in the middle picture is our 2013 Norton and the dot on the right is the 2013 Chambourcin. As you can see, the liquid has already migrated to just above the dots of wine.
Here’s how far the migration has gone an hour later. I won’t bore you with an hour-by-hour photo, don’t worry! Clyde will pull the sheet of paper out around 6pm tonight and let it dry. The liquid should have reached close to the top of the paper by that time. That chromatography orange liquid chemical-y stuff smells terrible by the way, so he’ll take it out of the jar while he’s outside!
Once it’s dry, we’ll end up with something that looks similar to this finished test. The picture above shows a test run on the exact same wines back on November 9. In this photo you see the 2012 Norton on the far right. This is the wine that has finished with it’s ML fermentation. See how there is a blob of white at the top, but lots of color in between? That’s what a finished wine should look like. Compare that with the middle streak (the 2013 Chambourcin) or the one on the far left (2013 Norton).
Since both of the wines show big blobs of white in the middle, this means that on Nov. 9, both the Chambourcin & Norton still hadn’t finished with the ML fermentation. Clyde is hoping that by now they are both finished. I’ll post up the results of today’s test here on the blog tomorrow. In the mean time, feel free to take bets on whether it’s finished or not!
While he’s running tests on the wine, I’m doing my own test today. I’m trying out my own twist on pumpkin pie using some Whittenburg. Plus I’m trying out names for this pie….’Whittenkin Pie’, “Whumpkin Pie”, or in keeping with the malolactic namers – “Pureed Pumpkin and Spices with Whittenburg Served in a Pie Crust”. Whatever I end up calling it, I’ll bring you the recipe and pictures later this week. Cheers!
(P.S. For My Dad – I took all these pics using our phone’s camera since the other camera was tied up with Pumpkin Pie.)