The unique mushroom flavour

Mushrooms have a rich, savoury flavour, much loved by consumers, chefs and cooks the world over. What is it that makes mushrooms so tasty? It is the natural glutamates in mushrooms that give them their deep flavour, making them a favourite with meat eaters and vegetarians alike.

Glutamate is an amino acid that is found in all foods with protein. Glutamate is also produced by the body, with high levels in the muscles and the brain. Glutamate is used as a neurotransmitter in the brain by half of all nerve cells.

The glutamate level in the mushroom increases as the mushroom matures from a button to a flat mushroom. Natural glutamate is also responsible for much of the flavour in parmesan cheese, soy sauce, anchovies, tomato juice, Vegemite and Marmite.

Umami history

Umami is a Japanese term first coined by Kikunae Ikeda, professor of physical chemistry at the University of Tokyo, in 1908 for the taste of a broth made from seaweed, dried fish and shiitake mushrooms (Chen 2009, Kurihara 2009). Umami is the colloquial Japanese term for “tasty”.

We often hear that the range of tastes in food include salty, bitter, sweet and sour. Foods with natural glutamates provide a fifth taste, now called umami, describing a food that has a savoury or meaty taste. It appears that the combination of glutamate and a savoury odour links both the taste and smell neural pathways in the brain, resulting in a very pleasant flavour. (Rolls 2009)

Potential role of glutamate

Glutamate is a major fuel for the gut. Glutamate is extensively metabolised by the intestines and therefore, not all of it is absorbed by the gut (Burrin 2009). Glutamate is a signaling molecule in the nervous system of the intestines. The intestinal metabolism of glutamate probably occurs mainly in the enterocytes in the epithelial cells of the intesitinal lining (Burrin 2009). Free glutamate may also be absorbed via the stomach and be involved in the digestive function, such as contractile actions of the intestines, gastric acid secretion and blood flow.

Certain proteins, called hydrophobins, are found only in mushrooms and these proteins contribute to the texture of the mushroom, making eating them so enjoyable. It is the combination of natural glutamates, protein and other natural flavour compounds that makes the mushroom texture and flavour so pleasurable.

You can now see why mushrooms are the flavour that everyone enjoys and they are a very successful substitute for meat. We sometimes consider mushrooms as the meat-eaters vegetarian choice. It also helps understand why mushrooms complement so many meat dishes.

The natural free glutamates in mushrooms are not to be confused with the monosodium glutamate (MSG) sometimes added to foods as a flavour enhancer. There is no MSG in mushrooms. In fact, with mushrooms in the meal you probably don’t need to use salt or flavour enhancers.

References:

  • http://www.ific.org/publications/brochures/msgbroch.cfm
  • Burrin DG, Stoll B. Metabolic fate and function of dietary glutamate in the gut. American Journal of Clinical Nutrition 2009; 90 (suppl): 850S-856S
  • Gibney MJ, Macdonald IA, Roche HM. Nutrition & Metabolism. The Nutrition Society. Blackwell Publishing 2003
  • Kohlmeier M. Nutrient Metabolism. Academic Press 2003.
  • Chen QY, Alarcon S, Tharp A, Ahmed OM, Estrella NL, Greene TA, Rucker J, Breslin PAS. Perceptual variation in umami taste and polymorphisms in TAS1R taste receptor genes. American Journal of Clinical Nutrition 2009; 90 (suppl): 1S-10S
  • Kurihara K. Glutamate: from discovery as a food flavor to role as a basic taste (umami). American Journal of Clinical Nutrition 2009; 90 (suppl): 719S-722S
  • Maga JA. Mushroom flavour. J Agric Food Chem 1981; 29 (1): 1-4
  • Rolls ET. Functional neuroimaging of umami taste: what makes umami pleasant? American Journal of Clinical Nutrition 2009; 90 (suppl): 804S-813S

 

 

 

Nutritional information:
Mushroom, ham & rocket pitta pizzas

Recipe Image 1
Protein 30g
Fat
17g
Sat Fat
7g
Carb
55g
kJ
2070
B1 0.58mg
B2 0.53mg
B3 15mg
 
 
Copyright - Australian Mushroom Growers' Association - last updated May 27, 2011