Tuesday, September 22, 2009

Report: With higher rain and fewer degree days, harvest promises to be a bumpy ride for vintners

I've been sharing excerpts from the monthly e-letters that Mark Chien, who is Pennsylvania's wine grape educator, sends to his clients and friends. Some of the terminology and subject matter can get more technical than many novices want to or can absorb, but for those like myself who share an interest in all that goes on to produce the wine, it's meaty stuff. Plus it often makes you realize just how many hurdles these folks jump over to turn out each year's vintage.

Mentioned in other recent posts how bad the season has been for most grapes; just too much rain throughout much of the state. And that's what Chien references in one of the items that came via e-mail on Monday.

I've been stuck in the mud as far as posts these past couple weeks. Have three or four interviews to get up, but between work and school and a nasty cold, I'm behind on things. Worst part is trying to stay away from alcohol and, thus, not drinking any wine. Well, maybe the worst part was having tickets to the Maryland Wine Festival in Westminster this past weekend and being too sick to go. Kevin, we'll try again next September.

Anyway, Chien writes:

The weather has improved but by no means is this vintage out of the woods. Dry periods like we are experiencing are great for putting the brakes on disease conditions, if only temporarily and moving the physiology of berry ripeness forward. The conditions of this vintage are pretty much etched in stone and even with good weather we won't make much brix progress. I think the idea now is to push fruit as far as possible to gain flavors, phenolic balance and drop acid, especially in red varieties.

All of your work with disease control, canopy management, crop adjustment, etc are either paying dividends now are maybe indicating what should have been done but if the work isn't done by veraison [Editor's note: the terms for when wine grapes change color], it is mostly too late to catch up. Gazing at fruit chemistry data from our colleagues to the north (statewide NY data in their Veraison to Harvest newsletter) it is pretty certain, as you have surmised by now, that we are staring at a low sugar year. The data from the Lake Erie Regional Grape Program is even more scary - current degree days are 24 days behind 2008 and a whopping 33 behind '07. It's hard to quite know what to do about making still wine in these conditions.

But low sugar doesn't have to mean low flavor and-or balance. I remember vintages like this in cool-rainy Oregon and one of the nicest Pinots we made came in at 19.5 brix. I think in a cool vintage like this one good wines are more about flavor and phenolics and not as much about sugar. In cool conditions getting the necessary heat to the berries to synthesize flavor and phenolic compounds is a struggle and every effort should be made to warm the fruit (see attachment).

Alcohol can be "fixed" with careful chapitalization to bring balance and texture to the wine. Chapitalization is a science and art and you should ask experienced wine makers how and when to ameliorate a wine. The biggest cellar problem I have heard about so far is high pH and high acid grapes. This is a real cellar conundrum. Wines that suffer from this imbalance can have awkward texture and suffer from "Eastern twang", that sensation you get when in your mouth when you play a Jews harp. You'll have to find a really experienced enologist to tame a wine with this problem. . . . The duty of the grower right now is to get the grapes in as clean as possible. At least if the grapes aren't fully mature the wine maker won't have to worry about diseased fruit and off flavors. That might not be easy, even if the sun continues to shine.

Downy and powdery mildew on leaves and even phomopsis on fruit are all a continuing concern, even more if the rain starts again. The rots are all out there, if not already fully expressed in tight clusters then in latent form just waiting for the right moment. There isn't much you can do at this point but to keep the fruit zone very open and hope for sun, dry conditions and a nice breeze. When the rot starts to spread, consult with the wine maker about the threshold for damaged grapes. Ideally he or she should be out in the vineyard tasting grapes with you. Whites are more forgiving of rot than reds so the wine maker might let white varieties hang a little longer. But if the grapes are mired in bitter, ripe or sour rots, you can't push them too much further before they turn to mush that has no hope wine.