Finally the Lab

Why does that word sound sexy to me? I believe I've turned into more of a geek than I realized. Wonder what Freud would have to say? OK that probably came across as completely random, but Gilles and I ended up in a discussion about Freud today. I suppose that sounds random too. But this is one of my favorite things about working with him. Interesting topics aren't avoided or skirted the way they are in the average American conversation. Granted I'm generalizing a lot, but what I can say for certain is that find myself at ease in that honest way I usually do around Europeans. I think it has a lot to do with their sensibilities... For instance Gilles' manner is somewhat akin to the person who tells you that you have spinach in your teeth while you're at the dinner table by just saying it rather than subtly gesturing while no one is looking. It's refreshing.

Anyway today is the day. Gilles announces that we're heading to the field to take some samples. First we establish which plot is to be sampled (that whole following-a-map thing again). Then start at a row and count about 10 vines in before beginning the sample. This is because the vines at the end get more sun, are more ripe, so picking them would throw off the numbers. We want a field average.


Then march straight up to a random bunch of grapes, tear off a handful in the most indiscriminate and haphazard way possible and throw them into the gallon sandwich baggy that you've pre-marked with a sharpee.


The key is to not look at the bunches as you lay into them. Kinda like looking away from the fish as you rip the hook out of its mouth I'm thinkin. It's actually so that you get a true representation of all levels of ripeness in that plot - green, ripe, tiny, plump etc. As Gilles puts it, some people are pessimists, others are optimists and this will be reflected in the numbers later (by how ripe or unripe the grapes are), which is basis for the decision to harvest. I'm thinking he said a mouthful there! Life seems to give you what you perceive right...

OK then walk up the row a ways and grab from the other side, looking away from the bloody carnage. Work your way all the way up that row, choose a random row further down and work your way down wreaking the same destruction. Apparently some winemakers get all precise and anal about looking for equal amounts of different grapes. Others will go into the vineyard and take their refractometer with them and start testing grapes. There is absolutely no way to get a plot average that way.


Now we bring them back to the cellar and squish them (technical terminology).


Pour the juice into plastic cups that you've pre-marked with the plot names and record the numbers into the log for later entry into the computer.


A mini discussion on pipettes. Not only do I love this word, but it's particularly endearing with a French accent (what isn't). These are glass straws of various widths that you use to suck the juice and or chemical compound that you're wanting an exact measurement of, i.e. 5ml, 25ml etc. A word of obvious wisdom - suck gently, there are somethings you really don't want in your mouth. I'm talking about chemicals you freaks!


Let's talk about what exactly we're measuring. #1) The brix - degree of sugar #2) the TA - titratable or total acidity and #3) the pH - you're thinking I'm going to explain this one?

#1) The brix is measured with a refractometer using mirrors and light to measure fructose and glucose. Other sugar compounds are not important for our purposes.


#2) The TA is measured by colometry (sp?). Here goes. Start with 200 ml of distilled water, which as any good geek can tell you, is not absolutely neutral. Add 5 ml of phenolphtelein (whom we'll call feefee), a color indicator that doesn't affect the pH. To get the distilled water to absolute neutral, add a few drops of dilute base (alkaline), which shows up pink thanks to our lovely feefee. Now add 5 ml of the squished juice (which of course is acidic). Then titrate with sodium hydroxide until the liquid turns the same level of pink as it was when you had when you added the base. Write down the number of ml of sodium hydroxide used and multiply that by 1.53, which gives you the g/L of tartaric acid in the grapes! Whew!

OK now the English version. I'll attempt to summarize the process the way I understand it, which isn't saying much. My apologies to any chem geeks who already get it. Essentially you're taking the water to neutral - by adding dilute base - so that you have a blank page. (Geek moment and news flash to me. Apparently even distilled water is not neutral, and if you want to get crazy to nth degree, there is no such thing as 100% neutral water unless you have millions of $ worth of equipment and you find this stuff fun.) Then you're adding acid - the grape juice - which tips the pH scale to the acidic side. Next you're adding enough base - the sodium hydroxide - to tip the scale toward the alkaline side until you get back to neutral again. The number of ml of the base solution - sodium hydroxide - it took to get the water back to neutral is multiplied by 1.53 because the molecular weight of tartaric acid is 153g. The resultant number obviously reflecting g/L of tartaric acid. Metric system anyone?

Sorry no picture of this one.

#3) The pH is measured by a pH meter. This lovely piece of equipment has so far made me crazier than I already am. The f____n thing isn't accurate in my opinion. But according to winemaker geek logic, the very fact that it fluctuates in its numbers every friggin second is an indication of just how absolutely accurate it is! Uh huh. Wouldn't you be screaming? Because apparently the thing is alive, or it's measuring fluid which is always alive, or something else Gilles told me about being alive that I seem to have blocked out of my immediate memory. It has to be calibrated every day and the thing is more sensitive than a woman on her period with a full moon! Gilles uses words like "gentle" "feel" "hunch" "wait" and my favorite "patience" - it's a MACHINE! Alright clearly I'm on a rant and am offering nothing of substance here. Let's just say I'm in the process of learning to understand this one and I'll attempt a better explanation as I learn patience. Namaste, Ohm, and Peace Out!