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Monosoduim Glutamate
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[01:12.71]In today's lecture, Tm going to talk about Monosodium Glutamate, or MSG, as it’s more commonly known.
[01:20.47]Now, MSG as you probably know, is a flavour enhancer which is used particularly in Chinese and Japanese cooking.
[01:29.68]Today I am going to explore why it is so popular in these cuisines and, more importantly, how does it enhance the flavour of food?
[01:40.75]The main reason why MSG is more commonly used in Japanese meals is tradition.
[01:48.26]For many thousands of years the Japanese have incorporated a type of seaweed known as kombu in their cooking, as they discovered it had the ability to make food taste better.
[02:00.69]But it wasn't until 1908 that the ingredient in kombu which was responsible for the improvement in flavour was actually discovered to be glutamate by scientists working there.
[02:13.59]From 1908 until 1956, glutamate was produced commercially in Japan by a very slow and expensive means of extraction.
[02:24.89]It was in 1956 that the speed of the process was improved, and industrial production increased dramatically and still continues to increase to this day.
[02:36.21]In fact, hundreds of thousands of tonnes of MSG are produced all over the world today.
[02:47.85]So what exactly is MSG?
[02:50.56]Well, Monosodium Glutamate contains seventy-eight point two per cent glutamate, twelve point two per cent sodium and nine point six per cent water.
[03:02.99]Glutamate is an amino acid that can be found naturally in all protein-containing foods, erm, so this includes food such as (Q35-Q36)meat and cheese.
[03:14.87]It is widely known that Chinese and Japanese food contains MSG but many people don't seem to be aware that it is also used in foods in other parts of the world.
[03:25.80]For example it is found in commercially made Italian pizzas’ in American fast food and in Britain MSG is used in things like potato crisps.
[03:37.34]So, how exactly does MSG work?
[03:40.91]Well, in the Western world, we commonly talk of four ‘tastes’, and Tm sure you're all familiar with the concepts of sweet, sour, bitter and salt.
[03:52.91]Well, in 1908, Kikunae Ikeda identified a fifth ‘taste’.
[03:59.22]And it is thought that MSG intensifies this naturally occurring ‘taste’ in some food.
[04:06.20]It does make perfect evolutionary sense that we should have the ability to detect or taste glutamate because it is the amino acid which is most common in natural foods.
[04:19.56]John Prescott, an associate professor at the University of Chicago, suggests that this fifth taste serves a purpose just as the other tastes do.
[04:29.87]He suggests that it signals to us the presence of protein in food, in the same way that sweetness indicates that a food contains energy-giving carbohydrates.
[04:41.19]Bitterness, he says, alerts us of toxins in the food, while sourness warns us of spoilage and saltiness signals the presence of minerals.
[04:51.63]So, what else do we know about this fifth taste...

Question 31-33
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Choose the correct letter, A. B or C.

31.The speaker says the main topic of the lecture is

32.In 1908, scientists in Japan

33.What change occurred in the manufacture of glutamate in 1956?

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Question 34-40
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Complete the notes below.

Write NO MORE THAN TWO WORDS for each answer.

Monosodium Glutamate (MSG)

 MSG contains

- glutamate (78.2%)

- sodium (12.2%)

- (9.6%)

 Glutamate is found in foodie that contain protein such as  and

 MSG id used in foods in many different parts of the world.

 In 1908 Kikunae Ikeda discovered a

 Our ability to glutamate makes sense because it is so naturally.

 John Prescott suggests that:

- sweetness told us that a food contains carbohydrates.

-  tells us that a food contains toxins.

- sourness tells us that a food is spoiled

- saltiness tell us a food contains

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