Home cooking: Is science the missing ingredient?
From edible dirt to miso foam, the influence of science in high-end cuisine has transformed the way we think about food. But the gastronomic techniques used by top chefs are also possible to achieve at home, if you add a dash of science to your cooking.
Nicholas Kurti, a former University of Oxford physicist and food lover, famously commented in 1969: "I think it is a sad reflection on our civilization that while we can and do measure the temperature in the atmosphere of Venus we do not know what goes on inside our soufflés."
But science is no longer so far removed from the everyday kitchen. As Harold McGee writes in his classic text Food & Cooking: "Science has found its way into the kitchen, and cooking into laboratories and factories."
While the home cook may not be ready to reach for the centrifuge just yet, the application of a few scientific principles can help turn everyday dishes into something extra special.
So how do you create high impact recipes without the need for expensive equipment? Some of the world's food innovators share their knowledge.
Sous-vide salmon in your kitchen sink
Sous-vide cooking, meaning 'under vacuum' in French, is a popular restaurant technique that involves cooking food slowly in airtight plastic bags at very low temperatures. Most restaurant chefs using this technique invest in a sous-vide machine or water bath, which can cost an average of £250.
But in his latest book Modernist Cuisine at Home, former Microsoft employee turned food innovator Nathan Myhrvold offers a variation on the technique - using your kitchen sink.
"One way to do sous-vide is to have a water bath or immersion circulator which is a machine that has a digital thermostat.
Molecular cuisine at home
"We realised if you have a bunch of hot water, you don't really need it. It's particularly true of something like salmon where you have a thin fillet, or a thinly sliced steak. If you filled a sink or a pot full of hot water, as long as you don't put too much salmon in - there's enough heat stored in the water to cook the salmon."
Although the recipe requires very little equipment, it is worth investing in a digital thermometer says Mr Myhrvold, so that you can determine the temperature of the water.
Another benefit of sous-vide cooking is it allows you to cook tougher cuts of meat such as pork belly gradually over a period of several days.
"If you're willing to use this piece of new fangled equipment and you're willing to plan ahead a day or two, you get something that may come out medium rare or medium but it won't be grey or overcooked and it will be tender and it will have this amazing texture you've never had."
A perfect cheese melt
Food scientist Jennifer Kimmel has found a way to achieve a perfectly melted grilled cheese sandwich.
"The secret lies in understanding how the molecules within cheese influence the ooey-gooey melted goodness that is the essence of a perfect grilled cheese sandwich," she writes in the book 'The Kitchen as Laboratory.'
What is molecular gastronomy?
There is disagreement in the culinary world over what is meant by molecular gastronomy. Two experts offer their view.
Hervé This (Physical chemist):
As gastronomy means knowledge, molecular gastronomy is the right word for a science which considers phenomena occurring during the preparation and consumption of dishes.
People like Heston Blumenthal and others were completely wrong when they said that molecular gastronomy does not exist any longer. They are confusing molecular gastronomy (science) and molecular cuisine... which still exists.
Job Ubbink (Senior food consultant at Food Concept):
Molecular gastronomy carries both positive and negative associations: positive as it is seen as something exciting, in the context of innovative foods and dishes. Negative as it has come to be associated with a rather artificial style of cooking.
Science-based cooking or experimental cuisine would better cover the cooking part, as they highlight that it is about cooking, based on a systematic approach, on understanding and experimentation.
She points out that some cheeses have better melting properties than others. "An appropriate pH for the good melting of cheese is in the vicinity of 5.3 to 5.5.
"It of course depends on how the cheese is made, but in general this pH range balances the different protein interactions and allows for a good melt."
By using different varieties of cheese in one sandwich such as Gouda, Gruyere and Manchego, it is easier to balance the final cheese pH to achieve both soluble calcium and soluble protein, explains Ms Kimmel.
The result is a cheese that melts and flows when heated.
"A grilled cheese sandwich may be a mundane part of food but it becomes delightful when prepared correctly," says Job Ubbink, author and senior consultant at Food Concept and Physical Design in Fluh, Switzerland.
"It is important to show people how you can use some simple scientific concepts, in a condensed way to explain why things happen at a physical and chemical level."
Mr Ubbink says that molecular gastronomy has been misunderstood in recent years, as it tends to be associated with a style of flashy cooking rather than exploring the science of what happens during cooking and eating.
"If you want to prepare say a piece of meat you can use a thermometer to put into the meat which people have been doing from the 1970s onwards.
"But if you know why you have to stop there because it relates to protein denaturation in the meat etc. then you understand what you're doing and you can start experimenting without a recipe.
"I think that these insights are more important than techniques."
Extracting coffee using cream
While experimenting with new dessert recipes, Mr Myhrvold's team discovered that infusing whole coffee beans in cream in the fridge overnight allows you to extract the full flavour of coffee.
"We realised that a lot of the flavour compounds in coffee are fat soluble. So you were never going to extract all of them with something that didn't have some fat in it."
He explains that the fat portion of cream extracts the fat portion of the coffee, while the water part of the cream extracts the water-soluble part of the beans, so you end up with pure coffee cream.
Crack the perfect crème brûlée
"It gives you a coffee flavour that you've never experienced before."
Mr Myhrvold recommends making a custard out of the cream for use in recipes such as a crème brûlée.
Another variation on the recipe involves infusing beans in melted butter on a low heat to create coffee butter.
But rather than simply following a recipe, Mr Myhrvold hopes to inspire home cooks to develop variations of their own.
"One of the things we wanted to do is to show home cooks that you don't have to slavishly follow a recipe," he says.
"We want people to look at a recipe as a jumping off point for lots of other things."
Understanding the science of food is just as important as mastering elaborate techniques, he says. As it allows you to be much more experimental in the kitchen.
"It's about exploration…. and doing cool and interesting things that will amaze you yet are still very practical to do at home."