Smell Blind: The Asparagus ‘Bouquet’ Phenomenon, Or Why Your Pee Smells Funny (and Why You May Not Smell it)

Cynthia Belliveau is dean of Continuing Education (CE) and Distance Learning and faculty in Nutrition and Food Science at the University of Vermont. In June, CE will host the second annual Food Systems Summit, which includes a public conference on June 27.

asparagusFor most people, the fresh, strong, grassy flavor of asparagus symbolizes the onset of spring. True enough, but if you also don’t also associate asaparagus with the strongest urine smell on earth, your olfactory sense must be on the fritz. What happens in digestion that this delicious, elegant vegetable can make you want to spray air freshener immediately upon leaving the seat?

According to the 1975 study by chemist Robert H. White at the University of California at San Diego, this “asparagus urine phenomena” is caused from s-methyl thioesters – or in quasi-layperson’s terms, odor-causing compounds.

“It” smells like grassy sulfur within 10 minutes after consumption. For those of you who eat asparagus and haven’t experienced this “bouquet,” here’s why: Recent research studies show that although everyone produces the smelly compound in their urine, only 22 percent can smell it. This is because only 22 percent of us have the genetic trait, or the one-single gene within a 50-gene cluster of olfactory receptors, that can pick up the odiferous tones of these delicate spears. The rest of the population – and lucky for them – are smell blind.

So for the 78 percent who can’t smell it and of the 22 percent who don’t care, here is one of my favorite asparagus recipes. It’s a classic. While you are at the market shopping for asparagus, remember that thin is not better. In fact, those thin spears are young and stringy while the thick ones are older and far more succulent. If you are in Burlington, Vermont, go to the Farmer’s Market on Saturday mornings and head right for Jane Pomykala’s stall for the most delicious, thick asparagus you’ve ever tasted (she also sells at City Market).

Jane has “old” beds as she calls them that have produced for decades and are at the peak of perfection.

Now, back to the recipe. Asparagus likes to be paired with starches, like pasta, or rice, or potatoes. Starch is the perfect complement base for the stronger tones of asparagus. A bit of salty meat and a dash of cream all tossed with linguine and cheese make for a mouth-watering spring treat.

Asparagus with Prosciutto and Linguine

(Serves Four)

Preparation time – 15 minutes


  • 1 pound of linguine
  • 1 pound of thick local asparagus (cut bottom end off is it feels tough), cut into 2 inch pieces, separating the spear tops.
  • 1/8 pound thinly sliced prosciutto (or ham), finely chopped
  • 1 tablespoon of butter
  • 1 tablespoon of olive oil
  • 1 cup chicken stock
  • 1 teaspoon salt
  • Liberal amounts of black pepper
  • 1 cup heavy cream or light cream for thinner consistency
  • 1 cup grated Parmesan cheese (best if you grate it yourself)


  1. Boil water for pasta. When water comes to a boil, add the asparagus, bottom pieces first and cook for three minutes and then add the rest and cook for another three minutes. Test as you go to determine the consistency you like.
  2. With a slotted spoon, take the asparagus out and set aside. Return the greenish asparagus water (full of vitamins) to a boil and add linguine. Stir the pasta around with a fork. Remember, pasta likes to “swim,” so make sure your pot is big enough for it to do so!
  3. While your pasta is cooking, sauté the ham in the butter and oil until crisp on medium heat. Stir in stock, salt and pepper (always taste as you go) and cook, uncovered for 10 minutes or until somewhat thickened. Test to see if your pasta is done. Drain and set aside. Once the sauce has thickened, add the cream to heat only.
  4. In a bowl, add the pasta and asparagus, and toss with sauce and 1/3 cup of Parmesan (leave the rest for the table). Taste for salt. You can always add more cream if you want more sauce.
  5. Serve immediately with a salad of spring greens.

Bon appetit (and let me know if you smell the difference later)!

I eat this versatile dish for lunch, for dinner with a green salad, and as a side dish with roasted meat. It’s ideal picnic fare, too, since it will keep at room temperature for several hours with no ill effects, which is what you want in a fresh summer dish.

Posted in: Health.