Hang time, like the name suggests, refers to the amount of time that wine grapes hang on the vine for after the growing season, during harvest. Harvest is the time when the grapes reach their peak of ripeness, but hang time goes beyond what has traditionally been considered peak ripeness. Hang time allows the grapes to dehydrate slightly, which concentrates flavors and boosts sugar levels. At first thought, this seems like a win-win as grape growers are producing the best grapes and vintners have flavorful grapes with loads of sugar, but that isn’t actually the case. There is a huge debate regarding the hang-time for grapes in viticulture, with one side stating they prefer to get paid per pound for juicy and ripe grapes and the other stating they should let the grapes hang for longer, even if they lose moisture, weight and volume, because they will have a better flavor in the finished wine. Here, we are going to look at the history of hang time, what happens to the grapes and how hang time affects wine grape prices, growers and vintners.

History of Hang Time

While hang time has gained popularity since the 1990’s, it isn’t a new practice. Not only are wine grapes left to dry slightly on the vine, some are even left until the grapes are hit by the first frost to make Eiswein, which makes a very sweet, concentrated wine, as the water is frozen when the grapes are pressed. The newer trend of hang time became popular during the 1990’s when vintners and wineries were looking for advantages in winemaking that would allow their wines to standout, as wines made from grapes that have a longer hang time are intensely flavored. Hang time, like other viticulture techniques, is a result of changes in wine-making and drinking trends.

How Hang Time Happens

Hang time can mean that the wine grapes are simply left hanging, but unless the weather cooperates, the grapes won’t reach the optimal brix, combined with the loss of water. The growing season for grapes typically lasts from early spring to the end of summer, then the grapes need to be harvested before the weather turns cold and rainy. Due to climate change, many regions experience longer and warmer growing seasons, and the heat at harvest spikes the brix level of the sugar, while also allowing the grapes to dehydrate. Ideally, temperatures begin to cool slightly with no rain, the grapes can hang long enough for the brix level to come up, without the loss of water.

Why Hang Time Isn’t Good for Growers

Wine grapes are an agricultural product, and as such, are sold by their weight. Wine grape growers have struggled to be able to break even, long before the demand for hang time grapes. In 2009, wine grape producers in California produced on average 3.3 tons per acre at a selling cost of $3,300 per ton, however, in order to break even, they would have needed to produce 6 tons per acre, or sell the wine grapes for their true value at $6,000 per ton.

Hang time brings down the weight of the grapes and places growers in a tight position where they are selling grapes that have a higher brix and more concentrated flavor for even less money per pound, than they would sell what would traditionally be considered premium wine grapes. While these numbers are a small sample from California, they represent a break even point that growers all over the world face. Prices for wine grapes in the crush market fluctuate widely from $100 to well over $9000 per ton and are often set at a regional level and factors including type of varietal, where the grapes are grown, brix level and tonnage are all considered when processors calculate prices.

Why Vintners Like Hang Time Grapes

Vintners like hang time grapes, as the extra time on the vine allows the grape to develop many characteristics that will produce exceptional wine with higher alcohol content. High-alcohol wines are another trend that has become popular in wines and promotes the longer hang time. Hang time improves the quality of the grapes by concentrating the compounds, tannins and flavors in the grapes, which allows vintners to create very flavorful and complex wines. The combination of flavor, high brix and alcohol produce wines that are very well received by wine critics and wine drinkers alike.

Hang Time Grapes Aren’t Perfect

Even with their highly desired concentrated flavors, there can be problems with hang time grapes. The higher brix level in hang time grapes, means more sugar for the yeast to convert during fermentation, and in the the worst scenario, too much sugar can create a stuck fermentation. When a stuck fermentation occurs, the yeast have converted so much sugar that the alcohol level is too high, and it kills the yeast before the yeast can convert all the sugar. When this happens, the fermentation can be revived through the addition of water. Many growers and vintners think that the addition of water cancels out half of the reason for leaving the grapes on the vine. And while hang time grapes present challenges during the wine-making process, there is question of how hang time affects the vine, Some viticulturists question whether leaving the over ripe grapes on the vine can create stress and weaken the vine over the long term.

What’s Going To Happen

As the debate continues over hang time, both growers and vintners need to consider all the long term benefits and risks of hang time. Research has to be conducted on the long-term effects of hang time on the vine, if hang time is harmful to the vine and growers and vintners need to work together to determine how to price hang time grapes based on their unique concentrated flavors and quality.

Hang time grapes and the wines they produce may only be a trend, but if they are here to stay there are still many questions that need to be answered if this practice is to become sustainable.