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For a long time, beetroots were one of the few foods I tried to stay clear of. I’ve never enjoyed eating the pure, basic boiled vegetable. Its earthiness put me off.
Until, I found out that, by tweaking just exactly how you prepare your beetroots, you can actually eliminate a lot of their earthiness!
Ever since, I’ve enjoyed beetroots. Whether it’s beetroot falafel, roasted beetroots, or even beetroot red velvet cake.
Geosmin makes beetroots earthy
It turns out, that earthy flavor isn’t something I imagined. It’s been described quite extensively by chemists. A main culprit? The molecule geosmin. This is an incredibly potent molecule, even a small amount can be detected by us humans and it’s to a large extent responsible for the earthy tones of beetroots.
Geosmin isn’t unique to beets. You can also find it in forest soil, after a period of rainfall. Hence, the ‘earthiness’. Wines can also contain geosmin, where it’s generally made by undesirable microorganisms. However, in the case of beetroots, the geosmin is actually produced by the beets themselves, and is a natural part of their being.
Reducing beetroot’s earthiness
The best strategy to reduce earthiness seems to be to hide the earthy flavor, geosmin is quite stable.
Acid hides geosmin
When pickling beetroots, you’re adding acid to the beet. This acid can provide a more balanced flavor profile of the beetroot, making it taste less earthy. A positive side-effect is that the acid also helps preserve the beetroot’s bright red color.
Peel the beetroots
The peel of the beetroots contains relatively higher contents of geosmin than the inside of the beetroot does. As such, peeling the beetroot will reduce its earthiness.
Roasting reduces earthiness
Boiling beetroots can reduce the earthiness of beetroots. The heat may break down some of the flavor molecules, or they might leach out.
A more effective method though, is to roast the beetroots. When roasting beetroots you’re initiating a wide range of chemical reactions, such as the Maillard reaction. During these reactions a lot of other strong flavor molecules and aromas are formed. These can overpower the earthy tones of the beetroot, in a good way.
Frying ‘extracts’ geosmin
Interestingly, very little research has been done on the impact of preparation methods on the earthiness of beetroots. However, for wines, where it has the potential to spoil large batches, more work has been done.
One way to remove the geosmin in that case was through extraction. By mixing the wine with oil, and then separating the two the geosmin would transfer from the wine, into the oil.
Personally, I found that deep-fried beetroot falafel doesn’t taste earthy at all. It’s quite possible that I’ve effectively extracted just enough of the geosmine into the oil, to remove the earthy flavor. Of course, during deep frying the Maillard reaction takes place as well, so again a lot more flavor molecules have been formed which can help to hide the earthy undertones.
Choosing a low-geosmin variety
Not every type of beetroot contains the same amount of geosmin. Some naturally contain more than others. Manufacturers of beetroot colorants may decide to use only those red beets that contain a relatively small amount of geosmin to limit off flavors. Most consumers want their food coloring to give color, not flavor.
Non-earthy beetroots preparation methods
Despite there being so little evidence in the literature for the best way to reduce the earthiness of beetroots, out of personal experience, I’ve learned that roasting and frying are great ways to do so, with pickling at a slightly distant second spot. The beetroot falafel recipe below is a surefire way to make a delicious non-earthy dish!
Aarika Chilson, Hate Beets? Science May Have the Answer Why, Just Beet It, June 1, 2021
Lisanti, Maria Tiziana & Gambuti, Angelita & Genovese, Alessandro & Piombino, Paola & Moio, Luigi. (2014). Earthy off-flavour in wine: Evaluation of remedial treatments for geosmin contamination. Food Chemistry. 154. 171–178. 10.1016/j.foodchem.2013.12.100.
BETHANY CLAIRE RICHARDSON, IDENTIFICATION AND CHARACTERIZATION OF POTENT ODORANTS IN SELECTED BEET ROOT (BETA VULGARIS) PRODUCTS, Thesis, 2013, link
Dhrubo Jyoti Sen, Moist earth smelling geosmin as a terpene bicycic alcohol, World Journal of Pharmaceutical Research, Volume 5, Issue 8, 01-08. 2016
Tyler, Lucia & Acree, Terry & SMITH, NANCY. (2006). Sensory evaluation of geosmin in juice made from cooked beets. Journal of Food Science. 44. 79 – 81. 10.1111/j.1365-2621.1979.tb10009.x.