Tuesday, February 10, 2009

Umami, you sexy!

Dear reader, I feel it is incumbent upon me to inform you about umami, the fifth sense of taste. You may have heard of umami already – it is a buzz word in culinary circles in the western hemisphere, even though it is old news in much of the eastern hemisphere. Unlike other, lesser food writers, I will not just inform you about the history and scientific nature of umami, but I will also instruct you on how to utilize this knowledge in your kitchen in view of improving the flavour of your food and, ultimately, the quality of your life.
Umami is a hot topic in the western hemisphere because scientists confirmed its existence only very recently – in 2001 to be exact. Yet, the concept of umami is one century old. A Japanese chemist called Kikunae Ikeda first documented umami in 1908. Professor Ikeda was intrigued by what made dashi – a broth made with a type of seaweed called kombu – so delicious. Ikeda was gifted with a highly discerning pallet; in dashi, he was certain that there was a taste component that was neither sweet, nor sour, nor salty, nor bitter. He eventually isolated a substance that was unusually abundant in kombu and that appeared to stimulate this fifth taste: monosodium glutamate (MSG). He noticed that the flavour of many savoury foodstuffs was enhanced when sprinkled with this substance. Hence, he dubbed the taste MSG imparted umami, Japanese for “delicious”.
Ikeda immediately embarked on a mission to save Japan from the blight of blandness by finding a cheap way of producing MSG. Within a year, he discovered that large quantities glutamate could be obtained by fermenting wheat gluten. The fermented gluten, when mixed with brine (water with lots of sea salt) would yield monosodium glutamate – the glutamate from the gluten would bind with the sodium ions floating in the brine. He began to market the product under the name Aji-no-moto or “the essence of taste”. The product took most of East Asia by storm and the humble chemist became a very wealthy man.
MSG did not cross the Pacific until after the Second World War. According to legend, American soldiers stationed in Japan, tired of Uncle Sam’s rations, began trying some of the rations the demobilized Japanese army had left behind. They found the Japanese rations to be absolutely delicious! Undoubtedly, this was because they were loaded with umami-tingling, MSG-laden treats. Upon completing their tour of duty, the legend goes, the soldiers went back to America with a collective addiction to instant ramen noodles. It would not take long for instant ramen, and their magic ingredient, to follow the soldiers back to the land of apple pie, where both would proliferate rapidly.
Initially, Americans, or at least the burgeoning American processed food industry, embraced MSG with great zeal. Alas, the honeymoon with this magical substance, which had the power to impart flavour to even the blandest can of soup, ended abruptly in the late 1960s. A Chinese-born American physician, Dr Ho Man Kwok, wrote a letter to a medical journal in 1968 in which he described a set of symptoms that he experienced whenever he ate at a Chinese restaurant. The symptoms, which began appearing within 20 minutes of starting a meal, included “numbness at the back of the neck, gradually radiating to both arms and the back, general weakness and palpitations…”. Interestingly, Dr Ho did not implicate MSG as the cause of these symptoms. Other scientists and the media began investigating other reports of similar symptoms; the phenomenon was soon dubbed “Chinese Restaurant Syndrome” (CRS). MSG, a substance used widely and generously by Chinese restaurants, was singled out as the culprit. Mass panic ensued. Bans and labeling requirements on products containing MSG soon appeared in several western countries. Chinese restaurants across the western hemisphere started offering no-MSG options (and, some claim, often using MSG anyway). Meanwhile, people in East Asia continued wolfing down truckloads of Aji-no-moto with reckless abandon, totally un-phased by CRS.
The hysteria surrounding MSG appears to be completely unwarranted. In the 40 years since Dr Ho wrote his letter, science has repeatedly failed to conclusively link MSG to any health problem. MSG’s bad rep in the west is undoubtedly related to the popular misconception that it is a synthetic chemical, like the many dyes and preservatives commonly added to processed food. Yet, the molecule at the heart of MSG, glutamate, is nothing other than an amino acid - one of twenty that make up the proteins in our bodies. In fact, our bodies produce it.
Glutamate abounds naturally in many foods, although most of it is locked within proteins. Some foods, however, contain significant amounts of glutamate on its own, not bound to any protein – called free glutamate. Kombu is one such food; there are many others (see Table 1). Generally, fermenting, curing, and cooking foods with protein-bound glutamate releases free glutamate and therefore imparts umami taste. Curiously, the consumption of Roquefort and Parmesan cheese has never been linked to CRS.

Understanding Flavour
Before I tell how to utilize this newfound knowledge of umami in your kitchen, I would first like to briefly discuss with you the basic science of flavour. An understanding of the rudimentary mental underpinnings of flavour will allow you to better manipulate this perception.
Flavour is frequently confounded with taste. Strictly speaking, taste is the aspect of food that you detect with your tongue. There are foods that have taste but no flavour – take pure white sugar or salt for example. We humans detect a total of only five tastes: the traditional four – i.e., sweet, sour, salty, bitter – and of course umami. To have flavour, a comestible item must simultaneously stimulate our taste receptors and our smell receptors (see Diagram A). Our smell receptors recognize thousands of different odors.
There are two distinct ways to heighten the perceived flavour of a foodstuff: (1) to heighten the taste or (2) to heighten the smell. Generally, the former is much easier than the latter, as we have access to odorless substances such as sugar, salt, and indeed MSG which can augment taste (and therefore the flavour) without altering the overall smell of a food.
Something very interesting happens when you pursue the first strategy. If you heighten only the taste of a food, you will perceive an increase in both taste and odor. For example, if you are eating bland strawberries and you sprinkle them with some sugar, their perfume will seem more vivid. The inverse also works: if you strengthen only the odor of a food, you will have the impression that it also has more taste. To use the strawberry example again, if you have fresh, ripe strawberries with a strong perfume, they will taste sweeter than bland strawberries even if the actual sugar content in both is the same.
So, by heightening any of the five tastes in a food, you will increase the flavour and you will have the impression that the food has more odor, or aroma if you prefer (see Diagram B). You are undoubtedly already accustomed to adjusting especially the saltiness and sweetness of foods. I encourage you to also learn how to adjust the “umaminess” of foods, especially savoury foods.

Umami in Your Kitchen
Adjusting umami in a savoury dish, just like salting, will extend the flavour of the dish (see Understanding Flavour). In fact, by increasing the umami in a dish, you can reduce the need for salting. (As you have probably been warned, your salt intake is likely to be inversely proportional to your lifespan.) Obviously, you could just add Accent, the North American brand of pure MSG, to your cooking. However, even though there may be no health risks, I do not advocate the use of pure MSG. Instead, I propose manipulating the umami taste through the use of ingredients inherently rich in free glutamate.
To maximize umami in your cooking, I warmly encourage you to follow two basic strategies:
  1. Know your free glutamate sources. Keep them stocked in your kitchen. This is your Umami Arsenal.
  2. Use multiple weapons from your Umami Arsenal. You can maximize umami taste by combining several free glutamate-rich ingredients. Its better to combine a few rather than to max one particular ingredient.
You can equip your kitchen’s Umami Arsenal with the following items:
  • cured meats: prosciutto, pancetta, bacon
  • cured or fermented fish products: anchovies, fish sauce
  • hard, aged cheeses: Parmesan, Romano, Asiago, old cheddar
  • plant-derived free glutamate sources: kombu, shitake mushrooms, soy or tamari sauce, Bragg’s, nutritional yeast, miso paste, tomato paste
Looking at this list, you can see why, for instance, Caesar salad is so delicious. It contains three umami bombs: anchovies, Parmesan, and bacon. Traditional miso soup also caries a nice umami payload: kombu, miso paste, and shitake mushrooms. Add some shoyu (Japanese soy sauce) or tamari and you will be blasted to a four-dimensional umami paradise.
Cured meats as well as anchovies can be used especially in soups and sauces. The process of making many soups and sauces begins with sautéing aromatic vegetables, particularly onions and garlic. Before adding the vegetables to the pan, you can add a small amount of one of the cured meats listed above, finely chopped. You can also add a few anchovy fillets, which will dissolve in the oil on the pan within a minute or two. Do not fret about using anchovies – if you add only a few filets (say, three or four), they will not taint your dish with a fishy smell. Note that both cured meats and anchovies are salty; when you are seasoning your dish, be careful not to add too much salt.
Even if you disdain animal murder, there are still interesting avenues for enhancing your soups and sauces. In your case, you may wish to add kombu and shitake mushrooms to your vegetable broth. Neither of these ingredients need be restricted to the realm of Japanese cooking. Throw them into any oriental or occidental soup or sauce the same way you would throw in aromatics, such as bay leaves or thyme.
Umamilicious hard cheeses are generally added to a dish just before serving but they can also be blended into a dish at an earlier stage. Parmesan in particular is well suited for this. I especially enjoy adding a small amount of grated Parmesan to salad dressings. The Parmesan tends to dissolve in the olive oil and thickens the dressing. Yes, a thick and extra delicious dressing!
When seasoning any dish, I urge you to consider using a few drops of fish sauce in lieu of salt. Just as kombu and shitake mushrooms have a place beyond Japanese cookery, fish sauce too should flow freely beyond the cuisines of Thailand and Vietnam. Did you know that fish sauce was once quite at home in Europe? Garum, as it was called in Latin, was all the rage at the height of the Roman Empire. A few drops of this pungent potion in a soup or sauce, and even in a salad dressing, will tremendously enhance the flavour. Do not be turned of by the pungent smell that will emanate from your dish when you first add fish sauce – it will mellow with time. But do not overdo it either – add it in small amounts, a few drops at a time. Stir for a few moments, taste, and repeat if necessary. If your sense of ethics or general squeamishness prevents you from using fish sauce, apply soy sauce or Bragg’s in the same manner.
Dear reader, I could prattle on like this for several more pages. I think that this will have to do for the present installment. I am confident that I have convinced you of the paramount importance of the umami taste and that you will now take every opportunity to maximize it in your food. Take the above ideas and experiment a little bit. Get a feeling for the items in your Umami Arsenal. Free that glutamate!
Good appetite.


  1. Brilliant article. Especially enlightening regarding the bad rap of MSG - its a shame so many "natural" chemicals are misunderstood. It's further fascinating to me that MSG could be classified as a 5th taste and isn't just a "flavor enhancer", but your argument seems to make sense... I wonder, if in the same way that "sweet" is the taste of sugar, "salt" is the taste of fats, and so on - our senses of taste have evolved for a purpose, to help us recognize the raw materials rich in energy and organic biomolecular building blocks (N, C, H, O), i wonder if in the same way, MSG may be linked to certain microbes (bacteria/fungus) that are found on all the examples of foods rich in Umami/glutamate....?

    On another note, I have read some research in evolutionary biology that suggests that our distant hominid ancestors found foods rich in "accessible" glutamate (i.e. as you point out, not locked in proteins) and other sugars and fats to be rich sources of energy - considering that in most environments if food wasn't scarce it was still a challenge to hunt and/or gather foods that were edible and digestible, it is feasible that our neurological reward systems evolved to appreciate these little packets of tasty energy... and such a perspective goes a long way to explain society's obesity problem today, as in an environment where food is technically plentiful, our attraction to fats and sugars is no longer an evolutionary advantage in natural selection.

  2. Ooh - this is why I have Marmite for breakfast every morning!

  3. It's nice to know you've gone beyond our one-time conversations of "fat=flavour"

  4. http://www.salon.com/food/nutrition/index.html?story=/food/feature/2010/03/17/msg_huffington_post

  5. Great article. FYI the traditional ceasar salad has no bacon.