The system removes objects such as insects, skins, raisins, shot berries, stem jacks, petioles, leaves, and other MOG from the product flow, before wine goes into a fermentation tank.
Prior to its launch, Key Technology carried out trials at wineries in North America, Europe, and Australia and the system has been installed at Pepper Bridge Winery and Chateau Ste. Michelle in the US.
Improves quality of the wine
“If it’s not removed, MOG will release a bitterness – a harsh tannin – to the wine. Removing the non-grape attributes like this will improve the quality of our wine,” said Jean-François Pellet, winemaker, Pepper Bridge Winery.
“We can receive, sort, and crush three-and-a-half tons of grapes per hour with four workers. One is overseeing the operation, one is feeding product to the system, and two are sorting out leaves before the destemmer.”
The stainless steel machine can roll into position under a destemmer so that the fruit flows from one machine to the other.
It sorts up to five tons (4.5 metric tons) of red grapes per hour.
Quality control
“The technology allows us to use machine-picked grapes and put only berries and pure juice into fermentation. It gives us exceptional quality control to end up with a very rich and dense wine that doesn’t have the tannin from green stems and leaves,” said Ray McKee, red winemaker, Chateau Ste. Michelle.
VitiSort starts with a vibratory conveyor belt that shakes the grapes to separate the MOG, which fall through a slot onto a sloped surface for removal.
As the grapes fall from the end of the vibratory conveyor into the sorter a camera inspects each fruit.
A drip tray keeps juice out of the camera line-of-sight and the sorter analyses the images, comparing each object to previously defined accept/reject standards.
Air jet ejector
When the unwanted objects are identified, the sorter activates an ejector system, which is made up of air jets that remove it from the product stream.
The grapes are then discharged from the sorter into a trough or screw conveyor to take them to the fermentation tank.
“The MOG shaker is very effective at removing insects and shot berries, which reduces the load on the optical sorter and improves its performance. The optical sorter takes out stem jacks and other MOG,” added Pellet.
Key says the VitiSort comes with a color touchscreen control panel where the winemaker can adjust the sort parameters to remove more or less MOG to meet requirements and the product settings can be stored and retrieved.