Sweet, sour, bitter, salty and – ah yes, umami. It’s the somewhat ineffable savoury flavour that makes certain foods so moreish. It was first proposed as one of the basic tastes by a Japanese chemist named Kikunae Ikeda.

Ikeda realised that the seaweed broth he loved was so tasty in part because it had a pseudo-meaty quality. After some analysis of his dinner one day, he realised that it contained glutamate crystals responsible for this flavour. A stable form of the same chemical, monosodium glutamate – better known as MSG – was soon patented, branded as Ajinomoto, and used in food products all over the world.

In the year 2000, scientists discovered that humans have a specific taste receptor for that umami flavour which helps to explain the popularity of MSG. Cheese, bacon, and chips with ketchup also contain natural forms of glutamate that trigger the umami receptor – explaining why we often crave these super savoury foods.

Watch the video below to understand why we are born to love these foods, the truth about the risks of eating too much artificial MSG.

--

Follow BritLab's YouTube channel and join 700,000+ Future fans by liking us on Facebook, or follow us on Twitter, Google+, LinkedIn and Instagram.

If you liked this story, sign up for the weekly bbc.com features newsletter, called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Future, Earth, Culture, Capital, Travel and Autos, delivered to your inbox every Friday.