If you’ve never experienced the pleasure of visiting a vineyard right before harvest, you can be forgiven for wondering what the difference is between wine grapes and table grapes. Yet, those lucky enough to have plucked a juicy vitis vinifera grape straight from the vine, will able able to reply with a resounding “Well, actually, quite a lot now you come to mention it...”
Species & Varieties of Grapes
Before we look into the intricate details of what separates the wine grape from the table grape, it is important we understand a little bit more about the vines on which grapes are grown:
The Vitis (grapevine) is a fruit-bearing genus (subdivision) of the Vitaceae plant family. There are 79 species of Vitis vines, some of which are commonly used for the production of table grapes and others which are more suitable for the cultivation of wine grapes.
The most important species of grapevine, Vitis vinifera accounts for almost 90 percent of the world’s cultivated grapes. All of the familiar wine varieties belong to Vitis vinifera, as do many of the common table varieties. (Learn more in "The History of Vitis Vinifera.")
Other notable species of grapevine include:
Native to North America, Vitis labrusca is the source of many varieties of table grapes including Concord, Delaware and Flame Seedless grapes.
This species is more important for what it produces below ground rather than its fruit. Vitis Riparia roots are commonly grafted to Vitis vinifera vines, owing to their resistance to the aphid phylloxera.
Another native North American species, the Vitis rotundifolia variety is the source of the popular Muscadine and Cowart table grapes.
The Vitis aestivalis grape has been noted to be the oldest grape variety species of America which still remains in production for making wine. The vine is very hardy and can grow up to ten meters and is known to climb into high trees. It is highly prized for its natural ability to resist disease.
For wine production, the grape has certain characteristics as low acidity with a good tannin structure and "wild" aromas and flavors.
It was the rootstock from this vine that was used during the Great French Wine Blight to save the declining vineyard industry in France due to an infestation of phylloxera brought on by imported American vines. The grafting was a success, prevented diseases and is still the only known prevention method for phylloxera. (Read more in "How the Great French Wine Blight Changed the Global Wine Industry.")
Wine Grape vs Table Grape Comparisons
There are many aspects to grapes that separate wine grapes from table grapes including their size, skin thickness, flavor, contents and their methods of cultivation.
Size & Shape of the Grapes
Most people may thing that wine and table grapes are similar in size, however, they really aren't. Wine grapes are very small and spherical in shape while table grapes are large and can be spherical or oblong in comparison.
The thick skin found on wine grapes is vital for producing deep color and intense tannins. Table grapes, on the other hand, contain lighter-colored, thinner skin allowing for a more pleasurable sensation when consumed, which brings us to the next topic of flavor.
Wine grapes are chosen for their intense, concentrated flavor. High levels of sweetness and acidity are essential during winemaking, with sugar being converted to alcohol and acidity vital for balancing the overall flavor of wine. Table grapes are much less intense in both areas, noticeably so when tasted alongside wine varieties. Because of their thinner skin and plump pulp, they are juicy and sweet, with their cultivation being aimed at providing a fruity flavor rather than introducing tannins and other elements needed for future use during the wine production stage as wine grapes are. (Read on in "How Do All Those Aromas and Flavors Get Into Wine?")
Seeds and Pulp
The ideal table grape will contain very small seeds, or better yet, no seeds at all - some are even genetically engineered to not produce seeds. In the production of wine, however, seeds are an important source of tannins. Wine grapes, therefore, contain large, hard seeds. They also contain a much higher juice-to-pulp ratio than table grapes, perfect for maximizing yield from the vineyard to the winery. The thicker pulp found in table grapes provides a meatier fruit, perfect for eating. (Read "The Anatomy of the Grapevine Explained.")
The manner in which wine grape vines are managed varies greatly from that of table grapes. Wine grapes are grown with the intention of maximizing concentration within the fruit and this is achieved through rigorous and planned pruning, resulting in comparatively low yields of fruit. Table grape growers, on the other hand, are not as concerned with reaching the exact levels of maturation and concentration required in the production of high quality wine grapes. Thus, their vineyards produce much higher yields of grapes that can be harvested earlier in the season.
And there you have it - the definitive guide to which grapes are ideal for eating, but more importantly which grapes provide us with that sweet, sweet nectar we call wine!