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1 .In today's lecture, I'm going to talk about Monosodium Glutamate，or MSG, as it's more commonly known.
2 .Now, MSG, as you probably know, is a flavour enhancer which is used particularly in Chinese and Japanese cooking.
3 .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?
1 .The main reason why MSG is more commonly used in Japanese meals is tradition.
2 .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.
3 .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.
1 .From 1908 until 1956, glutamate was produced commercially in Japan by a very slow and expensive means of extraction.
2 .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.
3 .In fact, hundreds of thousands of tonnes of MSG are produced all over the world today.
1 .So what exactly is MSG?
2 .Well, Monosodium Glutamate contains seventy-eight point two per cent glutamate, twelve point two per cent sodium and nine point six per cent water.
3 .Glutamate is an amino acid that can be found naturally in all protein-containing foods,
4 .erm, so this includes food such as meat and cheese.
1 .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.
2 .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.
1 .So, how exactly does MSG work?
2 .Well, in the Western world, we commonly talk of four 'tastes', and I'm sure you're all familiar with the concepts of sweet, sour, bitter and salt.
3 .Well, in 1908, Kikunae Ikeda identified a fifth 'taste'.
4 .And it is thought that MSG intensifies this naturally occurring taste in some food.
5 .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.
1 .John Prescott, an associate professor at the University of Chicago, suggests that this fifth taste serves a purpose just as the other tastes do.
2 .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.
3 .Bitterness, he says, alerts us of toxins in the food, while sourness warns us of spoilage and saltiness signals the presence of minerals.
1 .So, what else do we know about this fifth taste...