Courier Staff Writer
Wines start precisely where you probably think they do: On the vines. But getting them from the vine to the bottle depends on just who is doing the work.
Two area wineries, Cedar Valley and Tassel Ridge, take different approaches that highlight both the differences in philosophy and scale that wineries must address. How a winery harvests its fields helps explain what the winery wants to be.
There are two fundamental approaches to harvesting the field. The traditional method relies on hours of painstaking work by people out in the field who clip each bunch by hand. Technology offers much faster methods, but has its own risks.
Brock Bass harvests grapes for Tassel Ridge Winery, which taps technology to speed its harvest. The vehicle Bass drove to harvest the grapes bore a strong resemblance to a combine with the conveyor belt that drops harvested fruit into a container that is pulled down a parallel path.
The key difference between what the wineries use and a traditional combine is that there’s no cutting happening. You can’t cut down vines to get at the grapes when it takes 3-5 years for them to produce a good harvest in the first place. Instead, the harvester shakes the vines.
The harvester rolls down the rows with a central chamber that rides around the vines. Arms in the chamber shake the vines, causing the grapes to fall into a collector that blows away any leaves that might fall, then moves them to the waiting trailer.
The process is quicker than hand harvesting by a wide margin. But it’s touchy. Too hard and the grapes fall off before the harvester ever makes it to them. Too gently and the grapes won’t fall at all.
So Bass winds up making minute adjustments every couple of rows, depending in large part upon what the driver of the collection vehicle sees happening up ahead.
“We’re still just learning how to use this,” Bass said.
Hand harvesting still prevails at Cedar Valley. It’s much slower, but the grapes don’t come off the vines until someone physically has their hands on them.
The catch, aside from the much slower speed, is that hand harvesting also removes the mechanized means for removing leaves and other debris that may come with the bunches. Seth Miller, part of the family that runs the winery, said that’s important.
The leaves can impart an unpleasant taste if they’re left with the grapes during the crush. Getting them out by hand takes, you guessed it, more time. But it’s critical if the flavors of the wine are going to be what the makers envision.
Cedar Valley’s harvesters fill large plastic buckets with the grapes, which are brought to the crush location and sent back to the fields once the grapes are removed. The crush takes more time than it does to fill the buckets, so there’s usually a backlog of grapes waiting on harvesting days.
The processes that follow harvesting vary depending on what the winemaker is looking for in a finished wine. In every case, yeast is used to transform the sugars into alcohol.
Mike White, a viticulture expert with the Iowa State Extension Office, said white wines are pressed and the juice is separated directly into fermentation tanks. Red wines have an additional several steps.
A red wine requires the grapes and the juice to stay in contact, at least for the first stages. White said wine makers de-stem the grapes and crush them, then pump both juice and grapes into a tank for primary fermentation.
A second press about a week later separates the juice from the grapes for good. The juice goes into a different tank with more wine yeast for its final transformation into wine.
The process is tweaked for different types of wine. Red and white are the basics, but there are also rosés, blends, ice wines and, of course, sparkling wines.
Ice wines are made from grapes that freeze on the vine, a step that naturally concentrates the sugars. Sparkling wines, including champagne, have carbon dioxide dissolved into the liquid to produce bubbles.
“There are so many different types of wines,” White said.
All of them get their start in the fields with work that is far less attractive than the finished product. In fact, Bass said, it can be downright tedious:
“Once you get over the romance of harvesting grapes, it’s actually kind of boring.”