Hang time is hotly debated

A "hot" topic, these days, especially in California, is ”hang time”. hang time means how long the (ripe) grapes are left hanging on the vine before picking. Hang times influences several things: “ripeness” of course, which implies e.g. the phenolic ripeness (tannins), acid levels, sugar levels etc. But it also influences the water contents, thus the weight (longer hang time means loss of water). And since many grape grower are paid per tonne it can mean a substantial loss of income. (Often, in California, the grape grower and the winery/wine maker are entirely separate and independent.) It is also a debate about what taste characteristics it leads to: longer hang time means more powerful, heavier, and sometimes jammy wines. And the tendency today is towards longer hang time. Some also say that the longer hang time often used today sometimes leads to too concentrated must which leads to that the Californian winemakers have to dilute their wines with water…
Hang time: www.napavalleyregister.com
Water into Wine in California: www.economist.com/intelligentlife/