This weekend we had one of our favorite summer dishes, asparagus and salmon. Fantastic, but the first way to the toilet left once again this terrible smell of the urine. I know for many years that’s normal after consuming asparagus and it is no problem connected to it.

This time I was keen to find out why it happens and what the story is behind this unusual smell. So I checked the internet, wrote to an old friend who is a medic and always able to help me out with good answers. Here are the results in short.

  Asparagus urine. Pic from tag24.

Myth asparagus urine.

Not every person’s urine smells of a kind of asparagus orgy. The scientists still do not know exactly which enzyme has to break down which substance, so that the typical smell is produced, but there are guesses. But it is quite certain that there are some people who do not possess the relevant enzyme due to a gene mutation and therefore do not even develop the extremely-smelling substances.

However, there are also people who pee very well asparagus urine, but just can not smell it. We have a large body of genes responsible for our sense of smell, and it may well be that small mutations allow us to miss a few nuances. This is not so rare and can also occur with the asparagus smell. It doesn’t matter if it is green or white asparagus.

  It doesn’t matter – both are smelling.

How did they find that out? It is not enough in this case, of course, to ask people only if they could find something mucky on the smell of their own urine. They also had to smell other people’s urine that had eaten either bread or asparagus. So it could be found that there are people who produce no asparagus urine (non-producer), although they ate asparagus and people who simply can not smell it (non-detectors).

  He knew about. „A few Stems of Asparagus eaten, shall give our Urine a disagreeable Odour…“ Letter to the Royal Academy of Brussels, Benjamin Franklin, c. 1781.

The pee mechanism.

Our urine is produced in the kidney. There, superfluous water with a lot of nutrients and minerals is pressed through a small filter system out of our blood. After this first filtration, the water enters a long pipe system with different sections. Each section is very clever and responsible for the reabsorption of certain nutrients. The water itself is also brought back into our body diligently, so that we excrete only about 1.5 liters instead of the initially filtered 180 liters per day. These processes can be influenced by hormones, so that our body manages to stay in balance, even if we absorb too much of certain substances.

  This is how most Germans like to eat asparagus. Some kind of ham, porkloin, steak as a side dish and garnished with young potatoes and Sauce Hollandaise.

In every person, this works with the pee in about the same. We eat asparagus and its chemical components are picked apart, broken down and transported by many enzymes. In asparagus, as in any other food, a variety of substances ends up ultimately in our urine. Only the substances that have a certain diameter are „freely filterable“ and can easily get out of our body. This does not include large proteins or glucose. By example, who pees sweetly, probably has diabetes and if the toilet water foams after peeing, there are too many proteins in the urine due to a disease.

  Yes, it can smell horrible. pic from tag24.

What smells ?

After the asparagus meal, scientists can detect a whole series of substances in our urine, which only came in there through the consumption of asparagus. It is very difficult to say which of the substances smell just as weird and from which part of the asparagus this substance was split off. It is believed that the odorless, sulfur-containing aspartic acid (asparagusic acid) to adventurous-sounding substances such as S-methyl-thioacrylate and S-methyl-3- (methylthio) thioproponiate is degraded. It can brake your tongue.

     This is how we buy it in Uruguay. Mostly imported from Peru. Fresh white asparagus is almost unknown and not available. This 450gram bundle was 361pesos, equal to 11.05USdollars, nearly 25,–US-dollars per kilogram. Similar prices as in Germany for „First Class White Asparagus“ !

Then the acid in the body turns into volatile sulfur compounds. When peeing these elements evaporate in the toilet and we shoot a very unpleasant smell in the nose. They are also sulfurous and sulfur is known to smell like rotten eggs.

Sulfurous flavorings in breast milk.

Here an interesting fact at the end. Breastfeeding mom’s with a great appetite for asparagus often have the problem that the infant does not like to drink their milk. The sulfurous substances can also pass into breast milk and do not taste and smell well to the little ones. Now you are informed.

  „I don’t like your milk“.

Some people now understand nothing because they have never noticed the strange smell. Because, as research done in 1987 revealed, about forty percent of the population are missing this enzyme. One found out that just a single gene, which is inherited, is liable.

Nevertheless, the asparagus should be savored, because its such a healthy and well tasting vegetable. Therefore we can overlook a bit of sulfur smell, right ?

  Who wouldn’t like a dish like this one. Freshly boiled white asparagus with slices of smoked ham and a sauce Bearnaise ?

Additional information.

China is by far the world’s largest producer of asparagus. In 2013 it produced 7.000.000 tonnes, followed by Peru with 383.144 tonnes and Mexico with 126.421 tonnes. U.S. production was concentrated in California, Michigan, and Washington. The annual production in Germany is about 100.000 tonnes from which are 92% white asparagus.

Click on pic to size up for a better view.

In the most parts of the world is white asparagus relatively unknown and therefore the demand very low. It is a specialty of Western Europe.

  What’s the difference ?

What is the difference between white and green asparagus?

Spring is asparagus time. Freshly stung he ends up at the stalls of the directly marketed asparagus farmers or in the store, discounter and supermarket. Who wants to save the trouble with the asparagus peeling already buys green asparagus, as this does not need the peeling. But what else is the difference between white and green?

  A feast ! Pan fried salmon on green asparagus with a relish of avocado, egg and „Frankfort Green Sauce“. Our guests enjoyed it very much. Serve a meal (its a very rich one) like this with a strong, dry white wine.

A lot of sun turns it green.

Green asparagus is like white asparagus a vegetable or common asparagus, botanically called Asparagus officinalis. Unlike white asparagus, green asparagus does not thrive in dams, but directly above the earth. As a result, it gets a lot of sun and forms the green leaf pigment, the chlorophyll. In addition, it grows faster than white asparagus and forms only a thin skin.

   Asparagus officinalis. Drawing from an old flora lexicon.

Turn green into white ?

So you just have to peel green asparagus, if at all, just above the cut surface, or just cut off the bottom part of the bar. In the taste green asparagus is a bit stronger than bright asparagus. And the green asparagus is richer in vitamins and other valuable ingredients. In theory, you can make white asparagus also green. Meanwhile, there are also varieties that were bred specifically for the cultivation of white and green asparagus.

Last Tip.

We like the green asparagus mostly pan fried or grilled on the BBQ. A friend sent the pic of a vegan dish – green asparagus on Filo-pastry with a coconut cream sauce.

    Our pan fried green asparagus with lemon and pepper.

   The Filo-pastry dish.   I have to try it !!!