To produce simply one bottle of white wine, about 600 grapes are needed. This might appear like a lot, but consider it-- a single grape doesn't yield very much juice. https://heathergreenphoto.com/?p=399 It takes about four pounds of grapes to make just one bottle of red wine.
site That said, the quantity of grapes needed to make wine can vary based on the type of grape, the size of the grape, and the white wine itself. Cabernet Sauvignon grapes tend to be much bigger than Chardonnay grapes.
The bottom line is that it takes a lot of grapes to make even a small quantity of wine. The next time you uncork a bottle, be sure to think about all the hard work-- and grapes-- that went into it!