Sunflowers
The sunflowers are a group of plants in the genus Helianthus. The genus is one of many in the massive daisy family, Asteraceae. Sunflowers are native to North America, with most of the species concentrated east of the Rocky Mountains.
Two species of sunflower stand out as the most important for culinary purposes. These are the common sunflower, grown for seeds and oil, and the sunchoke, cultivated for its large tubers. The common sunflower is native to the Pacific Northwest, occurring primarily east of the Cascade Mountains in the Inland Northwest. There are a few other native species in the region (Helianthus bolanderi, Helianthus nuttallii, and Helianthus cusickii), but these do not have culinary value.
Species
Sunflowers
Common sunflower (Helianthus annuus)
Sunchokes
Sunchoke (Helianthus tuberosus)
Common sunflowers
The common sunflower, Helianthus annuus, is thought to be native to the western United States and the Great Plains (into Canada). From there, Native Americans and European colonists expanded its range eastward. The wild form of the plant is still commonly found in its western range.
Sunflowers were domesticated in North America for use as a food crop starting 4,000 years ago. Wild sunflowers are heavily branched and have numerous smaller flower heads. The domesticated varieties were bred with a single large stem and flower head, and sizable seeds.
Spanish colonists brought the sunflower to Europe in the early 1500s. For the next two hundred years, they only found use in Europe as ornamentals. Seed production for oil didn’t take off until sunflowers reached Russia, where the plant was soon bred into specific varieties for edible seed and oilseed production. Today, Ukraine and Russia are the two top producers of sunflower oil in the world, accounting for over 60% of total production. In the United States, production is centered around the Great Plains, mainly the Dakotas. Production in the Inland Northwest is present but small. A warm-season annual, seeds are ready to harvest from late summer to mid-fall in the Inland Northwest.
Oilseed sunflower seeds are generally smaller, with black hulls, and a higher oil content. Those eaten as seeds are come from varieties with striped hulls and a lower oil content. These are called confectionery sunflower seeds.
In addition to oil, sunflower seeds are processed into sunflower butter (similar to peanut butter) or sunflower halva, a confection popular in Eastern Europe and Russia.
Like other seed oils, sunflower oil is often refined, deodorized, or winterized to increase the shelf life and smoke point of the oil. I’m personally not a fan of refined oils. Unrefined sunflower oil has a lower smoke point, but a great flavor.
Sunchokes
Sunchokes (Helianthus tuberosus) are grown for their large tubers that look like ginger root. This root vegetable is also known as a “Jerusalem artichoke”. The moniker is thought to have come from a substitution of the Italian name “girasole articiocco”. The name “sunchoke”, on the other hand, was invented in the 1960s as a marketing name. I usually don’t like marketing names, but I think it fits the plant very well - it’s a sunflower and it does have a flavor profile somewhat reminiscent of artichokes.
Sunchokes are considered by many to be a garden bully and difficult to remove once introduced into a garden. There are even people who claim the plant is invasive in its native range, where it spreads easily thanks to summer rains. Here in the Pacific Northwest, it is a little better behaved, but still very well-adapted to cultivation, achieving high yields with little effort or irrigation.
The plant, a perennial, is native to central North America. Prior to European contact, it was already in cultivation by indigenous people, who introduced it both east and west of its original range. Sunchokes were brought to Europe in the early 1600s, where it was quickly adopted throughout the continent. They eventually escaped from cultivation have naturalized widely.
In the US, sunchokes were commonly eaten during the colonial era, but eventually fell out of favor and only more recently regained some popularity here.
Cooking with sunchokes
Sunchokes are ready to harvest in mid to late fall and benefit from. Kept in a moist, cool environment, the tubers can last for up to five months. They can also be overwintered underground in most climates though in commercial production, they are dug up before winter. Many sources claim they taste better after a frost, and there may be the added benefit of reducing inulin content in the tubers (see section below).
The tubers can be eaten raw, in which case they are crisp and crunchy. They can also be cooked like other root vegetables. There is variability in the shape of the tubers. Some varieties are knobbier. Others are more elongated and smooth, and easier to peel. The peels are perfectly edible, but it’s a good idea to remove them if you’re making something like a purée or soup, in which case the peels will discolor the final product.
Making use of its high sugar content, a number of distilleries in the region surrounding Stuttgart, Germany, produce a liquor called “rossler” from sunchokes ("topinambur” in German). They are also pressed to make inulin syrup.
Inulin
Sunchoke tubers are high in a type of sugar called inulin. Sunchoke plants use inulin as their primary carbohydrate for storing energy in the tubers. Yacón, dahlias, and chicory are a few other plants that also do so. Like sunchokes, all these plants are in the daisy family Asteraceae. Camas bulbs, too, are high in inulin (but are in the asparagus family).
Enzymes in the human gut do not easily break down this sugar. Inulin passes to the lower intestinal tract, where it is metabolized by bacteria, which as a byproduct cause excessive gas and even gastric upset. Some people are more affected than others. Some people report no issues. I’m one of those people who absolutely feels the effects, so I set off to figure out how to avoid them, if possible. I find them hard to pass up as they are both delicious and easy to grow.
I’ve seen a whole slew of different solutions suggested, so I’m going to address each one. The goal with any method is to reduce the amount of inulin ingested. Most methods attempt to transform the inulin into a different carbohydrate, fructose.
First things first, it appears that the inulin content in sunchokes is highly dependent on the variety, ranging from 30% of dry weight to nearly 75%. Finding or growing the right variety for eating, rather than inulin production, would likely prove to be worthwhile. Unfortunately, I have not yet been able to find this information.
There are two methods that are frequently suggested that I am skeptical of.
The first is to boil the tubers in lemon juice or vinegar. Cooking in acid will hydrolize the inulin and break it down into simpler sugars. From a culinary standpoint, such processing will absolutely change the flavor of the final product. Of the two acids, cooking the tubers in vinegar is rarely recommended due to the harshness of the flavor it creates. That said, I have two issues with this method: first, I have not been able to confirm how much inulin is converted by boiling the tubers in lemon juice, and second, I am not sure how effectively, either, the acid in lemon juice actually hydrolizes the inulin. I lean towards being skeptical since hydrolisis of inulin is usually done with stronger acids than lemon. Currently, as far as I am concered, the success of this method is hearsay.
The second iffy method I’ve seen suggested is to only harvest the tubers late in the season. Unfortunately, harvesting the tubers from late-maturing varieties, or varieties that have enjoyed a longer growing season will give you tubers with more inulin than early-maturing varieties. Late-maturing varieties have more time to make and store inulin.
On the other hand, inulin levels drop in the tubers if they are harvested after the plant has died down and they have been sitting in the ground for a while. Keeping them in cold storage for about one to two months will the same effect. Storage causes the tubers to convert the inulin into other sugars. The amount, however, is not nearly as much as would be hoped, only dropping by 5 to at most 10% after several months.
Now, let’s cover some methods that work.
The method suggested by Harold McGee, and that mirrors the indigenous method of cooking the native camassia bulb, is to cook the tubers for 24-48 hours at a low temperature. This slow cooking converts the inulin into fructose, but it does change the flavor and texture of the tubers significantly.
Lacto-fermentation also transforms the inulin as it is eaten by the fermenting bacteria. With this method, the tubers retain their crispy texture and acquire a pickled flavor.
The final method, also suggested by McGee, is to remove the inulin with water. Inulin is highly soluble in water, especially at higher temperatures. When inulin is produced as a commercial product, it is extracted into water. For cooking purposes, then, the best approach to remove inulin should be to slice or otherwise mechanically process the tubers to increase the surface area, then blanch them in boiling water. Longer blanching in boiling water will remove more inulin, but will soften the tubers’ texture. This method should be appropriate for making mashed sunchokes or soup.
The crisp texture of raw sunchokes is desirable as well for certain applications. Unfortunately, soaking in cold water is ineffective because the solubility of inulin is effectively non-existent at low temperatures. However, based on the method used in commercial inulin production, blanching the tubers at a temperature of about 165°F for 45 minutes would reduce the inulin by about 80% and hopefully provide a crispy texture for “raw” applications, frying, and roasting. I’ll update this page again after I’ve done some testing.
Other species
Other possible species
Two other species, the Maximillian sunflower (Helianthus maximiliani) from the Great Plains and the giant sunflower (Helianthus giganteus) from eastern North America, reputedly have edible (but smaller) tubers that can be eaten. Information is very limited, but these two species might merit further investigation.
