Friday, June 11, 2010

Is Sunberry Poisonous?

Sunberry (aka Wonderberry) is a little purple berry in the nightshade family (Solanaceae), bred by Luther Burbank himself 100 years ago (Solanum guinense x villosum). I grew it last year both on my deck and in my research plot alongside another novelty purple-berried Solanum, Garden Huckleberry (S. melanocerasum or scabrum?).

The taxonomy of this family is far from figured out. Tomato (which you'd think we'd understand pretty well!) was removed from the genus "Lycopersicon" to join its potato and eggplant sisters in "Solanum" just a few years ago. The various species of "nightshade" are a total mess - no less because it's one of those names that Europeans threw around pretty loosely as they discovered new plants.

From what I can tell, the classic "deadly nightshade" of European folklore is Atropa belladonna (same Solanaceous family, different Solanaceous genus). Europeans also named multiple species in this family as "black nightshades." Certainly, not everything called a "black nightshade" is closely related, but there seems to be a core cluster of extremely genetically-diverse species associated with the European black nightshade, S. nigrum: including S. villosum, S. americanum (American black nightshade) and S. retroflexum (some claim this as Sunberry's "species") among others.

Depending on who you ask, Sunberry and Garden Huckleberry were either bred from African and European nightshades or simply ARE individuals of these species. To further complicate things, some people use these names (plus "Wonderberry") to refer specifically to certain wild nightshades, which of course is the whole problem with using common names in the first place! There additionally seems to be a lot of uncertainty over whether these different wild black nightshade species are actually poisonous or not in the first place.

The whole Solanaceae family is riddled with various poisonous alkaloids - some species more than others, and often in the foliage more than the fruit, but I haven't yet been able to find any publications that really sort this out. I'd bet there's a lot of variation in chemical composition within each species thanks to their diverse genetics and environments (especially as they've been tracked in circles all around the globe). It could be that much of their reputation is ill (or at least inconsistently) deserved. It doesn't take too many bad experiences to establish something as "poisonous" in a culture. Tomato, just thanks to its similar appearance to other nightshades, was planted as an inedible ornamental in Europe for years before people were convinced its berries weren't poisonous!

This all leads me back to the statistics I ran this afternoon. One of my side projects is to compare the chemical composition of various wild and domesticated Solanaceaeous berries. When I compared the "metabolic fingerprints" of a broad array of Solanaceous berries (using a solvent extract that picks up poisonous alkaloids), Sunberry was almost indistinguishable from the nightshade S. americanum (Garden Huckleberry fell in the main clump with a lot of edible crops and potato berries). I have a lot of work to do to validate this analysis and figure out which chemicals actually account for which differences before I can make any trustworthy statement on this but I thought it was pretty fascinating all the same. I find it hard to believe that a crop (even a novelty one) that's been consumed for 100 years is poisonous (especially since consuming similar alkaloids in green potato tubers makes people feel sick pretty quickly), but maybe my particular accession of American black nightshade is perfectly edible?*

Maybe we're like the early modern Europeans all over again with their tomatoes - writing off perfectly edible plants as poisonous?


*don't go test-tasting wild plants now. that's just stupid..

...besides, both Sunberry and Garden Huckleberry are, in my opinion, horrible, worthless crops.

I never appreciated abscission zones until I grew Sunberry. Ripe Sunberry berries refuse to obligingly pop off their pedicels when ripe. They usually goosh out their innards as you try to remove them, leaving you holding the little purple skin as the seedy-slurry drips from your fingers. Even if you manage to pick a handful, they don't have much flavor (though more than the willfully taste-free Garden Huckleberry). My boss and his wife tried to make Sunberry jam, but even after adding an absurd amount of sugar, the mixture refused to set.


(picture from Seed Savers - hopefully they won't mind since I plan on spending a small fortune there the first spring I have a yard)

17 comments:

  1. I grew a Seed Savers selection a few years ago, and made jelly out of it, and I can confirm that it is practically taste-free. On the other hand, I am here to tell the tale.

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  2. you didn't happen to test solanum pyracanthum or solanum atropurpureum? i am growing both of them this year and can't figure out if the fruit is edible. some sources say yes, some no, some maybe.

    solanum aviculare is another one that comes with mixed reports. although it seems PROBABLY not poisonous.

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  3. No, but they look like pretty cool plants!

    We grew S. elaeagnifolium, but it wouldn't set fruit. I don't know if those fruit are poisonous and would be surprised if ANYONE really knows (unless they were regularly consumed by aboriginal peoples).

    We still have a ton to learn about what's actually in our foods and their wild relatives.

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  4. I LOL'd at this: "they usually goosh out their innards. . ." :D Thanks for the fascinating read! I remember you mentioning ground cherries in some long-ago post. Did you ever do toxicity studies on those? Thanks.

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  5. Yep, ground cherries along with any other fruit I happened to mention were part of my research are included in this. I haven't gone far enough into the data to see what kinds of compounds we can see in anything but the sunberry though.

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  6. I've always felt that "Wonderberry" was the most outrageously hyperbolic appellation. Shame on you, Luther. The wonder is that anyone grows this damned weed more than once. I've used it as a pie filler (aka adulterant) and can confirm, like Jeremy, that it tastes of nothing much in particular. Ah, but I bet it's full of antioxidants and will be appearing on a superfoods list sometime soon. Yawn.

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  7. Just found your site--great! I'll be back.

    I recommend Jennifer Edmonds monograph: "Black Nightshades" http://www.underutilized-species.org/documents/PUBLICATIONS/black_nightshades.pdf Interesting speculation about Luther Burbank's Wonderberry.

    Also a nice write up on my favorite black nightshade, Chichiquelite. There is an interaction with soil or climate though, sometimes the berries are tasty and sweet, other times rather bland and not sweet.

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  8. I found a ferral wonderberry in my garden in 2010 that i think came with the mice. The leaves tasted like spinach. It's actually edible in it's ripe form late in the season, but if you try them too early (in ripeness or in the season) they do seem to have a slight taste to them that could be poisonous. I tend to think they are generally edible, but they could use a bit of breeding work to make them better.

    I also found a wild black nightshade in my yard that looked similar, but instead had orange dots, smaller leaves, and a glassy appearance when ripe, and this one WAS poisonous, because i tasted part of it's leaf and it gave me an instant headache.

    Here is a picture i drew that compared the two. The large leaf is the wonderberry with a dark dull berry. The small jagged leaf with the clear shiny berry is the poisonous one (with tiny orange dots missing from the picture). http://i1010.photobucket.com/albums/af224/keen101/science/leaf2.png

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  9. LOl...planning my garden for spring and I was considering Sunberry...guess I won't bother now..tganks for the consise information

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  10. Sunberries are quite edible. If cool, then the berries have a very peculiar sweet taste, not pleasant. If however, they are very hot having been in an extremely hot greenhouse in New Mexico, then they taste pleasant, and I imagine would go well with hot chocolate

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  11. The sunberry plant is found in every garden in Tamil nadu, India. The leaves are much sought after - they have a slight bitter taste. They are cooked with mung beans and coconut. It is supposed to cure liver problems.If there is a minor cut on the body, you can crush a sunberry leaf and apply the juice. It has healing properties.
    The green sunberries are salted and sun dried and used in cooking thorughout the year.

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  12. I'm growing some this year, God willing (from rareseeds.com). MANY people say these are the best kind! Too bad I can NOT turn to a good source to get the nitty-gritty on the nutritional factors of this type ("solanum burbankii"). Anyone making jam can can probably avoid the "runny" aspect by using pectin or gelatin. Lots of other fruits have the same type of need when making jam. I can't WAIT to taste-test the first ones grown on this farm in northern Missouri.

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  13. Thanks for this post! I have a couple of these plants in my garden, they are in flower right now. This is the first year I am growing this.

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  14. Ate some of these that my lady friend is growing in Albuquerque. I'm not sure where she got the seeds from, but she's been raving about them after growing them last year. She said they were here "go-to snack by the end of last summer." She's way into the Ayurvedic tradition, so perhaps that's where she heard of them?

    While not sweet, the sunberries do have a good flavor. It's very subtle, and she describes them as "earthy." I'd say it's an unsweetened fruity flavor. It tastes and smells like a fruit/berry, but the flavor is extremely mild with almost no sweetness or tartness. It's actually good.

    I'm curious about the nutritional properties of these little beauties. I wish there was more info online, but this was helpful - especially the comments. Thanks!

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  15. I have sunberries growing in my yard (from previous homeowner) and the taste is mild. If you gently twist the ripe berries off there is not so much squishing of the berries. I like to pick a handful in the morning, soak for a few minutes in hot tap water, then add to my granola cereal along with other dried fruits and nuts for a healthy breakfast. They look like small blueberries. I don't think I'd bother trying to make jam with them as you'd really need to pick a lot of them, they're seedy not juicy, and why add tons of sugar to something - just eat them raw!

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  16. 2 years later and this is the best information i can find. i bought seeds from rareseeds and am puzzled. My flowers are yellow, but anywhere i look, they're meant to have white flowers? who knows. also- everyone has said different things for flavor....oh well, guess we will wait and see!

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