The world of taste and how to manipulate it: molecular gastronomy

An introduction to the science and art of molecular gastronomy

By Pia Mayer

Everything has a distinct taste. An apple tastes like an apple, an olive taste like an olive and meat tastes like meat. But our tongue is only able to detect five different tastes: sweet, sour, bitter, salty and umami. While the first four are relatively well known, umami might be new to some people. The term was created by a Japanese chemist in 1908, called Kikunae Okeda, was used to describe a pleasant savoury flavour. All of us prefer different combinations of these basic tastes and it is a cook’s most challenging task to find the perfect combination of each to please their guests.

But if there are only 5 fundamentally flavours then how are we able to taste so many flavours and tell them apart? Well, we know what an apple looks like and therefore we know what combination of flavours to expect due to previous experience in tasting it. This is where molecular gastronomy comes in. Physicist Nicholas Kurti and physical chemist Hervé founded the term “molecular gastronomy” in 1988. But what exactly does it mean?

Let’s start with the term gastronomy. Under the term gastronomy we can combine nutrition, art of selecting, preparing and the serving of food. The behaviour of molecules in solids, liquids and gases is well-known and is integrated in the food preparation processes. You may think “Oh yeah I already know this! It’s called food technology and I can get a degree for that.” Well, not exactly! Molecular gastronomy is a mix of food technology, chemistry and physics sized down and expressed within the contents of a plate. It takes familiar tastes and presents them in new and adventurous ways.

Most of us have experienced at least one example of molecular gastronomy whether we know it or not. For example, bubble tea. The soft bubbles that pop in our mouths and have different flavours. The process to make such bubbles is called spherification, gel pearls of various sizes with liquid centres. This structure is adopted from caviar and can be achieved by dropping a flavoured base mixed with sodium alginate (a gum like substance extracted form brown sea weed) into a calcium chloride solution. As soon as the alginate gets in contact with the calcium chloride, gelation occurs. This process works from the outside to the inside of the droplet. The calcium chloride mix causes the long-chain alginate polymers to cross-link. The longer the pearls remain in the solution the firmer and less liquid the centre becomes. But not only pearls are possible. From jelly-shelled caviar sized bubbles, to recreating the shape of gnocchi, a wide variety of shapes are possible.

Another example is transparent ravioli. Instead of savoury filled ravioli in a pasta mantling, molecular gastronomy chef Ferran Adria created a sweet and transparent ravioli in 2009. A super thin oblate that looks like a plastic foil which can be filled with anything of low water content, looking not only amazing but also proving that we cannot always rely on our eyes to experience flavours. In the molecular gastronomy everything is possible. Even something that looks like an apple but taste like duck.

From Issue 17