Percentage soluble solid by weight (in Brix) is used as a primary measure of the fruit’s suitability for harvest.
Wine grapes are harvested at a range of soluble solids from approximately 17-30 degree Brix. In California, European grapes are harvested from June to October about 80 to 120 days after blossoming. North America grapes are harvested during September and October, about 90 to 120 days after blossoming.
Grapes are harvested by machine or hand. Bunch grape cultivates ripen their primary crop uniformly enough that an entire vine is harvested at one time.
This facilitates both hand and machine harvesting.
Hand harvesting
Hand harvesting is used for all table grapes and many wine and raisin grapes. The hand picking allows more selective picking because all grapes do not mature at the same rate.
There is less damage to the vineyard trellis and irrigation systems than machine-harvested fruit.
In hand harvesting the pickers use a sharpened grape hook or a knife to sever the peduncle. However, the disadvantages of manual harvesting outweigh its advantages. In addition to labor costs, and inadequate availability, manual harvesting is slower, stops during inclement weather, and seldom occurs 24 hours a day.
Mechanical harvesting
Machine harvesting grapes has many advantages and some disadvantages. Machine harvesting is much more economical and faster than the manual method.
It has been estimated that in Europe, mechanical harvesting reduces the time involved from 160 – 300 h/ha to 0,6 – 1.2 h/ha and the cost from 1600 – 2000 Euro/ha to 400 – 550 Euro/ha.
Grape harvesting
