In winemaking, bottling is the step that transforms wine into a finished product ready for sale. How exactly does this happen?
Firstly, bottling requires equipment. Bottles, corks, and caps can sometimes be bought locally, but bottling lines — the machines that fill the bottles with wine — often come from afar.
“There [are] multiple suppliers that build these machines, and typically they come out of Europe or Asia,” says Matt Moersch, CEO of Moersch Hospitality Group, which owns Round Barn, Tabor Hill, and Free Run Cellars in Southwest Michigan.
Not only are these machines expensive, but they are also high-maintenance, requiring mechanical knowledge and thorough cleaning before and after each use.
For these reasons, some wineries turn to a mobile bottling service. As long as the winery supplies bottles and wine, the mobile service can bottle their wine for them.
“It’s on a semitrailer,” Moersch says, “and basically, you hook your hoses up … and they bottle it for you.”
However, some wineries prefer purchasing machines and bottling their own wine.
“We decided to invest in a bottling line because we like the flexibility [with the] timing of when we can bottle, and you get a little more control over the process,” says Sean Noell, cellar master at Mari Vineyards on the Old Mission Peninsula.
Additionally, bottling lines often prove to be a successful long-term investment.
“[Our bottling line is] 20 years old,” Moersch says, “but it still works great.”
Although different bottling lines have different capabilities, bottling methods are generally the same across wineries.
“It’s a pretty standardized process,” Noell says.
He outlines this process in five main steps:
- The workers place the empty bottles onto the feeder belt, which moves along the bottling line.
- Depending on the complexity of the machinery, the bottles may be rinsed and gassed.
- The bottles go through the filler.
- The full bottles move to the capper.
- The now filled and capped bottles are labeled.
Let’s break that down.
Placing the bottles onto the feeder belt and later taking them off is typically a task for entry-level winemakers, but it requires more physical strength and stamina than you would think.
“You just need to be capable of lifting 35, 40 pounds, over and over again, all day,” says Brian Hosmer, winemaker for Chateau Chantal and Hawthorne Vineyards on the Old Mission Peninsula.
Once the empty bottles are on the belt, they may be cleaned. This step is not necessary, as the bottles arrive clean when they are bought. However, if the machine has this supplemental feature, the bottles can be rinsed to wash out any remaining dust or cardboard particles and blasted with nitrogen to deoxidize them, as oxygen in the bottles can make wine spoil.
The bottles are passed to the filler, which typically moves like a carousel, and are filled with wine.
At this stage, if the winemakers are bottling sparkling wine, the operation may not run smoothly without a counter-pressure filler. Chateau Chantal recently purchased a new bottling line out of Italy that has this special filler.
“If you don’t have the counter-pressure filler,” Hosmer says, “[the sparkling wine] will just foam up, and the machine will just not work properly.”
Because of the carbon dioxide, which causes the foam, sparkling wine fills the bottles more slowly than still wine. As a result, the bottling line’s maximum speed is significantly slower for sparkling wine than it is for still wine. This is why it makes sense for makers of sparkling wine to have a particularly fast-paced bottling line, such as Chateau Chantal’s new machine.
Besides having the counter-pressure filler, which Chateau Chantal’s old machine lacked, the new machine is about twice as fast as the winery’s previous bottling line.
“[Our machine] typically runs about 1,000 to 1,500 bottles an hour for sparkling wine, and it can almost double [that] — sometimes triple that — with still wine,” Hosmer says.
Once the bottles are filled, the capper seals the bottle with either a cork or a screw cap.
The winemakers may choose between a cork and a screw cap based on how quickly they want the wine to age. Screw caps tend to be more airtight, which slows the maturing rate of the wine. A cork, on the other hand, allows for more oxygen transfer, helping the wine mature.
The winemakers may also consider practicality, as screw caps are more affordable and sustainable, or they may be influenced by the preferences of their customers.
Ultimately, “there’s not a wrong way to close the bottle,” Noell says.
When the bottle is finally sealed, it is ready to be labeled — either by the machine or by the workers, depending on the bottling line — and shared.
“From when you harvest [the grapes] in the fall,” Moersch says, “[they’re] now finally a finished product.”