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Mechanical Grape Harvesters: Benefits and Concerns fingers (bow-rods) to compress and shake the grape canopy, shaking the grape berries off the
Mechanical Grape Harvesters – Benefits and Concerns
vine. There are also models of grape harvesters that shake the trunk to dislodge berries off the clusters. The bow-rods shakers are considered gentler on the vines and the trellis. The
As the available labor pool continues to decline in the California grape industry, more growers and management companies are considering the switch to mechanical harvest. Statewide, only 20% of the winegrapes are picked by hand (estimates vary) and this number is predicted to
mechanical harvest machines use these set of bow -rods placed in close proximity to each other on each side of the fruiting zone, oscillating at a high number of beats per minute. The rods float
continue to drop. While the majority of the winegrapes in our San Joaquin Valley is picked mechanically, concerns remain to adopt mechanized harvest statewide.
freely though the canopy as the harvester travels through the field, and as the canopy moves back
Hand Harvest
Kaan Kurtural, Ph.D.
Picking grapes by hand, although laborious, has the ultimate benefit of the reasoning and care of the human being, the most
Bronco Wine Company Viticulture Research Chair Fresno State
important advantage being the exclusion of rotten or unripe clusters. There is also the advantage of reducing grape damage (broken skins, etc.) with hand harvest. However, hand
and forth the grape clusters also oscillate and the berries pop off the vine and drop down to the vineyard floor. The fruit lands on a catching tray and is collected by collector buckets and
harvest has the disadvantage of putting a crew in the field during high daytime temperatures, lack of light for night harvest (or the added cost of
transported to a cross conveyor that sits high atop the rear of the machine. As the berries travel across this
harvest spot lights), and increased likelihood of premature fermentation
conveyor, large fans suck out leaves, pedicels, sticks, and other non-grape
and prolonged harvest. Mechanical Harvest
material. The grapes are then transported to a discharge conveyor where they are screened by a
Grape
A grape harvester is a tall machine that straddles the trellis and uses special
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fan.
The
fruit