There are a few wild grape species that contain toxic compounds and can cause poisoning if eaten in large quantities. However, the vast majority of wild grape species are not poisonous. Wild grapes belong to the genus Vitis and are native across North America, Asia, and Europe. Most wild grapes are safe to eat when ripe, though some have an unpleasant taste. Only a handful of Vitis species contain high enough levels of toxic compounds like tannins that eating them could potentially make you sick.
Wild Grape Species That Are Potentially Poisonous
Here are some of the wild grape species that contain higher levels of toxins and may be poisonous if eaten in excess:
Moonseed (Vitis riparia)
Moonseed is one of the more toxic wild grape species. It contains alkaloid compounds like dauricine that can cause nausea, vomiting, and convulsions if eaten. Moonseed grows in eastern North America. It gets its name from its fruits, which look like crescent moons. While not outright deadly, moonseed fruit and leaves should be avoided.
Riverbank grape (Vitis riparia)
The riverbank grape is another wild grape native to North America that contains potentially harmful levels of toxins like tannins and flavonoids. Eating large quantities of riverbank grapes may lead to vomiting, diarrhea, and other gastrointestinal distress. Riverbank grape has a sour, unpleasant taste which deters most people from eating a lot of it.
Bitter nightshade (Solanum dulcamara)
Bitter nightshade is often mistaken for wild grapes. It has purple vine-like leaves and berries that resemble small wild grapes. However, bitter nightshade contains solanine and other toxic glycoalkaloid compounds that can cause diarrhea, nausea, fever, and in severe cases, respiratory paralysis or death. Bitter nightshade grows in Europe, Asia, and North America.
Fox grape (Vitis labrusca)
The fox grape is not normally poisonous, but a mold called ergot sometimes infects fox grapes. Ergot contains toxic alkaloids that can lead to convulsions, hallucinations, and gangrene poisoning. Without ergot mold, fox grapes are perfectly edible and even used to make wines and jellies. Fox grapes grow mainly in the eastern and central United States and Canada.
Wild Grapes That Are Safe to Eat
Most wild grape species do not contain high enough levels of toxins to be poisonous. Here are some of the most common edible wild grapes:
Muscadine grapes
Muscadine grapes are native to the southeastern United States. They have a thick skin and sweet, aromatic pulp. Muscadines make very good jams, jellies, and wines. The grapes grow in small clusters and ripen to a dark purple color.
Concord grapes
Concord grapes were originally grown from the native fox grape species. They are now a very common grape used for juices, jellies, and wines. Concord grapes are safe to eat and have a characteristic “foxy” musky aroma. These large slip-skin grapes grow in clusters and turn deep blue-black when ripe.
Frost grapes
Frost grapes grow abundantly in the wild across eastern North America. They get their name from being able to withstand cold temperatures. Frost grape vines produce small sweet grapes that grow in loose clusters. They have a mild grape flavor with a bit of tartness.
Scuppernong grapes
Scuppernong grapes are a light green or bronze-colored Vitis rotundifolia species native to the southern United States. They are also called muscadine grapes. Scuppernongs have a thick skin, sweet juicy pulp, and distinctive musky taste. These grapes are often used to make wine or eaten fresh off the vine.
Summer grapes
Summer grapes are native to Asia and parts of Europe. They ripen to a black or dark purple color in summer. Summer grapes grow in compact clusters on vigorous vines. They have a sweet floral taste perfect for eating fresh or making jams and jellies.
Signs of Potential Poisoning
If you experience any of the following symptoms after eating wild grapes, it may indicate poisoning:
– Nausea, vomiting, diarrhea
– Abdominal pain and cramping
– Excessive salivation
– Vision changes
– Difficulty breathing
– Confusion, hallucinations
– Seizures
– Feeling excessive coldness or sweating
– Muscle weakness or paralysis
Seek medical attention right away if poisoning is suspected, especially if symptoms are severe.
How to Safely Identify and Harvest Wild Grapes
Here are some tips for safely collecting wild grapes:
– Use a field guide to positively identify the grape species. Some poisonous vines like moonseed look similar to edible grapes.
– Avoid grapes growing in potentially contaminated areas near roadways or factories.
– Only collect ripe grapes. Unripe grapes contain higher concentrations of toxins.
– Eat grapes right after harvesting. Mold can grow on stored grapes.
– Only eat a small amount at first to test for any reaction.
– Spit out grape skins and seeds, which contain the highest toxin levels.
Uses for Edible Wild Grapes
Wild grapes that are safe to eat can be used in the following ways:
Jams and Jellies
Almost all edible wild grapes make excellent jams and jellies. Concord grapes and fox grapes are especially prized for making grape jelly.
Juices
Wild grapes can be crushed and strained to make fresh grape juice. Concord grape juice is a popular juice made from the native Concord grape.
Wines
Muscadine grapes, scuppernong grapes, and fox grapes are commonly used in sweet southern wines. Other wild grapes also make flavorful regional wines.
Raisins
Leaving grapes to dry into raisins concentrates their sweet flavor. Wild grapes can be dried into nutritious raisin snacks.
Pies
Wild grape pies are a wonderful way to use up a grape harvest. Concord grapes and muscadine grapes make delicious grape pie fillings.
Vinegars
The juice of wild grapes can be fermented into grape vinegar. Concord grape vinegar has a nice mild fruity taste.
Grape leaves
Grape leaves from wild vines can be used fresh or preserved to make dolmas and other stuffed grape leaf dishes. Pick young tender leaves.
Nutritional Value of Wild Grapes
Wild grapes, especially American native species like muscadine grapes, Concord grapes, and scuppernong grapes, are very nutritious. Here are some of the nutrients found in wild grapes:
– Vitamin C – One cup of wild grapes provides around 20% of the RDI for vitamin C.
– Vitamin K – Important for blood clotting. Wild grapes contain up to 28% of the RDI.
– Antioxidants – Grapes are high in polyphenol antioxidants like resveratrol. These combat free radicals and inflammation.
– Fiber – A good source of fiber to promote digestion and heart health.
– Potassium – Essential electrolyte that supports nerve signaling and heart function.
– B-vitamins – Including thiamine, riboflavin, niacin, B-6, and folate. Help convert food into energy.
– Magnesium – Assists with over 300 enzyme reactions in the body.
– Vitamin A – Grapes contain carotenoid precursors to vitamin A important for vision and immune health.
Conclusion
Most wild grape species should not pose any danger and are perfectly edible. Only moonseed, riverbank grape, and berries infected with ergot fungus are potentially poisonous if eaten in excess. Stick to positively identified grapes like muscadines, Concords, scuppernongs, and fox grapes to be safe. Wild grapes provide a very healthy snack straight off the vine. They also allow you to make flavorful jellies, juices, wines, and dishes with their natural sweet flavors. Just take care to avoid overindulging on species that may contain higher toxin levels.
