umami- the 5th taste

WHAT IS UMAMI?

• Umami (oo-ma-mi) is a savoury taste, known as the fifth tasteIt is a subtle taste and blends well with other tastes

© British Nutrition Foundation 2010

DISCOVERY OF UMAMI

• Umami was discovered by Dr Kikunae Ikeda, from Tokyo Imperial University, Japan, in 1908

• He undertook research into Dashi, a traditional Japanese stock made from kombu (kelp)

© Umami Information Centre

GLUTAMATE & UMAMI TASTE

• Professor Kikunae identified the amino acid glutamic acid, which he isolated from Kombu seaweed, as the source of this unique taste

• Inosinate (isolated from dried bonito tuna) and guanylate (from dried shitake mushrooms) were identified as umami substances also

GLUTAMIC ACID / GLUTAMATE• Glutamic acid is one of the 20 amino acids necessary

for health. • Glutamate is found in protein-containing foods such

as meat, vegetables, poultry and milk. It is found in two forms in the diet:

• BOUND glutamate• FREE glutamate

Glutamate is the negatively charged ion of glutamic acid, found in the body or in salts of the acid

Only free glutamate can bedetected by the umamitaste receptors.

Only free glutamate can bedetected by the umamitaste receptors.

THE TRADITION OF UMAMISEASONING

• Garum, a fermented fish sauce, was an essential and valuable condiment in ancient Rome.

• Fish sauces are staple ingredients in southeast Asian cuisine.

• The English Worcester sauce is a ferment of anchovies, sugar, spices and vinegar.

• The soy sauce, dashi, beef and yeast extracts, and tomato ketchup are all means of enhancing umami taste.

GLUTAMATE SEASONING

Glutamate seasoning is made by fermentation - a process similar to that used to make beer, wine or vinegar

1. CARBOHYDRATE SOURCE: EG. SUGAR CANE

2. EXTRACTION OF SUGARS: EG. MOLASSES3. FERMENTATION: SUGAR IS FERMENTED

TO PRODUCE GLUTAMATE-RICH ‘LIQUID’4. SEPARATION AND CRYSTALLIZATION5. DRYING6. PACKED FOR USE IN FOOD PREPARATION

1

2

3

4

5

6

UMAMI – A BASIC TASTE• There are five distinct, basic tastes• Basic tastes are universal and cannot be created by a

combination of other tastestastes

BASIC TASTE

FUNCTION STIMULUS DETECTIONLEVEL %

Sweet Energy source Sucrose 0.5

Sour Organic acids; ripeness or spoilage

Acetic acid(vinegar)

0.012

Salt Minerals essentialfor fluid balance

Sodium chloride

(salt)

0.2

Bitter Harmful/toxins Quinine 0.00005

UMAMI Protein, amino acids

Glutamate /MSG

0.03

© International Glutamate Information Service 2011

HOW HUMANS EXPERIENCE THEIR FOOD ?


Taste receptors on the tongue and palaterecognize each of the five basic tastes.

For example, when the umami receptors come in contact with glutamate, this

Information is relayed by the vagus nerve to the brain where the umami taste is

recognized.

Recently researchers discovered glutamate-specific receptors in the

stomach. These receptors only react toglutamate and connect, by the vagal

afferent nerve, to the brain. This suggests that the detection of glutamate by the

receptors in the stomach may signal the presence of protein to the brain and enable the gastro-intestinal tract to

prepare for protein digestion.

(Yasumatsu et al, 2009)

ENHANCING UMAMI TASTE IN FOOD

• In essence increasing umami in food means increasing the level of free glutamate. This can be brought about in a number of ways:

1. Ripening2. Maturation3. Drying4. Curing5. Cooking6. Adding glutamate or glutamate-rich stock

WHY INCREASE THE LEVELS OF

GLUTAMATE IN FOOD?

1. To make food taste “balanced, rich & delicious”

2. To reduce salt3. To reduce fat content

EFFECT OF UMAMI COMPOUNDS IN FOODS

• Increased palatability (Prescott, 2001)• Enhancement of prepared meals and sauces for consumers,

both young and old• Increase the savoury flavour of food, stimulate salivary flow,

and add to the sensations of "fullness, impact, mildness and thickness“ (Ninomiya, 2003)

• Increased food intake in the elderly, and a number of nutritional and immune parameters (Schiffman, 2002)

UMAMI IN JAPANESE CUISINE


UMAMI AROUND

THE WORLD


SOURCES OF UMAMI

Sea food Meat

Kombu (seaweed) Beef

Katsuobushi (dried bonito flakes)

Pork

Niboshi (small dried sardines)

chicken

Macquerel

Prawns

Cod

Squids

Oysters

Shellfish

Vegetables Others

Tomatoes Parmesan Cheese

Mushrooms Green Tea

Truffles Soy sauce

Soyabeans Chicken egg

Potatoes Oyster sauce

Sweet potatoes

Chinese cabbage

Carrots


BREAST MILK & UMAMI• Of the 20 free amino acids in human breast milk, glutamic acid

is the most abundant, accounting for 50% of the total free amino acid content (Rassin et al, 1978)

• Steiner conducted a series of studies on facial expressions of neonates in response to stimulation with different tastes

(Steiner, 1993)– Neonatal human infants responded with a quiet and relaxed face when

ingesting distilled or tap water. – Sour taste always triggered nose-wrinkling, lip pursing and some gaping– Bitter-tasting solutions induced head-shaking, frowning, tight closure of

the eyes, depressed mouth-corners, wide mouth opening and tongue protrusion, leading to wide gaping and sometimes spitting and drooling.

– Sweet-flavored water always induced eager sucking/smacking and licking movements;

– An unseasoned vegetable-broth precipitated facial displays similar to those induced by sour tasting liquids

– monosodium glutamate (MSG)-seasoned vegetable broth triggered facial expressions very similar to those induced by the sweet taste

Umami Sweet Sour Bitter• These results suggest that glutamate is a palatable taste

stimulus for humans infants; by virtue of its presence in breast milk, it might conceivably contribute to the taste acceptability of this liquid


STUDIES• Glutamate taste and appetite in laboratory mice: physiologic

and genetic analyses (Bachmanov et al, 2009)– Two strains of mice (B6 and 129) were used– Given the many similarities between mice and humans in metabolism

and behavior, it is a small step to infer that genetic variation in glutamate metabolism may also exist in humans and may influence their glutamate preference, consumption and post-ingestive processing

• Sensory and receptor responses to umami: an overview of pioneering work (Beauchamp et al, 2009)– sensation aroused by MSG is distinct from that of the other 4 taste

qualities– synergy of the binding of MSG and 5’-guanylate to tongue taste tissue

gives this perception

• Umami and the foods of classical antiquity (Curtis, 2009)– Romans enjoyed numerous foods that are identified today as

containing significant amounts of natural umami substances and frequently used fish sauce as a condiment in their recipes

– Fish sauce imparted to Roman dishes a moderately salty, slightly fishy taste that combines synergistically with other foods to create the umami flavor

– A close study of the remains of the Roman city of Pompeii indicates that fish sauce was a thriving business that rendered the popular condiment accessible to people of all social classes

• The blood-brain barrier and glutamate (Hawkins, 2009)– BBB has two membranes: i) Abluminal and ii) luminal– BBB is virtually impermeable to the net movement of glutamate

from circulation into the brain

• Glutamate: from discovery as a food flavor to role as a basic taste (umami) (Kurihara, 2009)– Marked synergism between MSG and the nucleotides– large response to MSG and guanylate could not be inhibited by

amiloride, an inhibitor of the response to NaCl– breast milk contains free glutamate at a concentration similar to that

present in konbu dashi (≈20mg/100ml)

• Early milk feeding influences taste acceptance and liking during infancy (Mennella et al, 2009)– From the perspective of taste, infants who consume different types of

milk during early life are exposed to pronounced differences in levels and patterns of taste experience

• Can dietary supplementation of monosodium glutamate improve the health of the elderly? (Yamamoto, 2009)– Dietary MSG supplementation in elderly subjects experiencing

clinically significant gastric disorders might improve stomach function and overall nutrition

– Effects on salivary volume and IgA secretion and on stomach functions seem promising

• Multiple receptors underlie glutamate taste responses in mice (Yasumatsu, 2009)– In humans, unlike in mice, T1R1/T1R3 acts as an umami specific

receptor that can discriminate between umami and other tastes, and thus accounts for umami-linked preferences or discrimination

1. Glutamate is the purest taste of umami, the fifth basic taste. Umami taste receptors have a special affinity for free glutamate. 10 2. We consume between 10g and 20g of glutamate from our diet, of which glutamate from seasoning or condiments is less than 10%.

THINGS YOU

SHOULD KNOW ABOUT MONOSODIUM GLUTAMATE

- MSG

4. The body treats glutamate in exactly the same way whether it comes from the food we eat or is added as seasoning.

5. Glutamate is important for healthy metabolism, however most of the dietary glutamate we consume is used as fuel by the cells of the digestive system.

3. Monosodium glutamate brings nothing new to the diet; it is the sodium salt of an amino acid foundabundantly in protein .

6. Increasing the umami taste in food by increasing the level of free glutamate can result in salt (sodium) and fat reduced recipes which still taste satisfying.

9. The extensive body of research which exists about this widely used ingredient has been reviewed by independent scientists and regulatoryauthorities throughout the world - all have found MSG to be safe.

7. Replacing table salt with monosodium glutamate reduces the sodium content of recipes, as MSG contains one third of the amount of sodium.

10. Numerous well conducted scientific studies have failed to show a connection between MSG and adverse health effects. In fact, MSG gives thebenefit of umami taste.

8. Only a small amount of added glutamate is required to optimize umami taste; using more won't do you any harm but, as with salt, the food might not taste as good.

I


CONCLUSION

Umami is the 5th basic taste and umami compounds are present in all protein-rich foods. Umami foods

are gaining popularity in the West too.Umami condiments have been in use since the

ancient times and nowadays, its used in all the food industries. Glutamate in various forms of MSG, hydrolysed proteins etc are used extensively to

enhance the savory flavour of the food.Umami effect in foods can be helpful in improving the

diets of the elderly.

umami- the 5th taste

Documents

discovery of umami umami

umami taste receptors

umami protein

food taste

detection of glutamate

umami receptorscome

umami substances

levels of glutamate