Cooking Vetch Peas (Vicia sativa)

This Winter, I have been experimenting with common vetch (Vicia sativa) as a cover crop. I'm curious if anyone on this forum has any experience splitting and soaking vetch seeds for human consumption. Fava beans that are hardy enough to withstand Ohio Winters (USDA zone 5b-6a) seem to be hard to come by, so it would be nice to be able to grow a cold-hardy substitute for my continental climate to grow over Winter. I'm assuming that vetch seeds have to be hulled and split before consumption based on similar requirements for cooking dried split peas and fava beans, but I have yet to find any online references for cooking vetch seeds.

For anyone that is not convinced that vetch seeds can be eaten with proper preparation, there is a Plants for a Future article that says that the seeds are edible when soaked and cooked properly here. The article cites several books that are not available at my local library. The Wikipedia article for this plant also mentions that this plant was once widely cultivated for its edible seeds citing a book called Domestication of Plants in the Old World.

I found five other web pages that mention the edibility of common vetch here: wildfooduk, here: sarcraft, here: tcpermaculture, here: scottishwildflowers, and here: eatthatweed Australia. Three of these five articles mention that some processing is required before eating fully ripe seeds from common vetch. The article by the Australian author seems to include the most information about food preparation required before eating vetch seeds, but he remains cautious about eating vetch seeds given the lack of documentation on how to properly cook these seeds.

The best information on how to process and cook common vetch seeds most likely comes from people who have actually eaten these seeds with no ill effects. So far, I have yet to find any blog post by a forager or gardener with convincing evidence that the author has successfully cooked vetch seeds, eaten them, and survived with no ill effects. Perhaps there are some forum members here who have experience using vetch seeds for food outside of the plant's application as a cover crop.

Hi Ryan,
You're a brave man!  I suppose if you're growing them anyway then eating the seeds isn't such a faff.  In terms of food value I would think you have plenty other legumes that would be perennial in your climate (alfalfa is a common one).  I would file it under "interesting but not worth the risk/effort".
I haven't tried Vicia sativa, but I concurr with Mark on Galloway wild foods that Vicia sepium young leaves make a nice nibble, although I haven't tried cooking with them, I am encouraging its spread for foraging.

Hmm... Don't know about V. sativa, but the seeds of many vicia species contain canavanine, which can induce autoimmune disease if eaten in quantity. PFAF seems to not know/care about this risk, since they list V. cracca (tufted vetch) as edible without known hazards, even though it definitely contains canavanine. Supposedly soaking and cooking can reduce content of canavanine and other non-proteinogenic amino acids, but not sure if it removes them completely... Feels like risky business to me.

I've done some further reading this afternoon and I found one journal article here that suggests a 90% reduction in plant toxins for vetch seeds when the whole seeds are cooked in a pressure cooker or autoclave for eight hours. The other methods tested in this article (roasting, soaking, hulling) did not have any significant effect on the level of plant toxins in the vetch seeds.

Given the lack of availability of pressure cookers in neolithic times, there must have been some other method of food preparation used for vetch seeds when this plant was still widely used as a source of food. I did some further reading later this evening and found another journal article entitled Neurotoxins in a Vetch Food: Stability to Cooking and Removal of γ-Glutamyl-β-cyanoalanine and β-Cyanoalanine and Acute Toxicity from Common Vetch Legumes. The article suggests two methods for removing toxins from split vetch seeds: either leech the toxins from split vetch seeds in a container of cold water over an eight day period changing the water daily or simmer the split vetch seeds in boiling water for three to four hours and change the water hourly. Both methods reduced toxins in the vetch seeds to undetectable levels. Unfortunately, this second article is paywalled so I cannot share much more of the contents here.

It took quite some time to find these journal articles. Given the fact that the detoxification procedures presented in the second journal article closely resemble the same procedures used to cook bitter lupin beans (Lupinus sp.), I'm surprised vetch isn't more widely eaten as a human food.

I've found them growing here in USDA zone 8b, tried one raw last spring... no good super stiff & chewy so I spit it out. Personally I think ever if you were to cook them you would have to grow a ton to get any amount that adds up to anything meaningful food wise.