Hydrocolloids, liquid nitrogen, centrifuges, thermal immersion circulators—it all sounds like it belongs in a science lab, doesn’t it? But you’ll find all of these materials in the kitchens of high-end restaurants across North America.
The use of these materials stems from a subdiscipline of food science called molecular gastronomy, which essentially investigates the physical and chemical transformations that occur within different ingredients during cooking processes. Molecular gastronomy can be further broken down into the sub categories of molecular cooking—which means cooking with modern tools—or molecular cuisine, a modern style of cooking that utilizes technical innovations from scientific disciplines.
Molecular gastronomy is a relatively new term that was coined by the late Nicholas Kurti, a former physicist at Oxford University and French chemist Hervé This in 1988. Chefs continue to put their own spin on these practices, which have brought a new element to the dining experience, as the techniques involve the senses beyond taste.
“It’s a combination of amusing, surprising and sometimes kind of unsettling,” says NAIT chef instructor Maynard Kolskog, referencing famed chefs like Ferran Adrià of elBulli and Grant Achatz of Alinea as examples of masters in the craft. “That’s what they set out to do: give you an experience. It’s like going out to the theatre. They’re going to wow you and sometimes they’re going to unsettle you with some of the things they give you, but they always want it to be delicious.”
“It’s pushed me in the sense that I look at food differently,” says Ben Staley, chef at North 53, who was first exposed to molecular gastronomy while working at the Blue Pear, then honing his skills through research of Adrià’s work. “I can look at an ingredient and go, ‘What can I do with this? … So I never think of a dish and think of how can I make this dish using a technique? We make a dish and say, ‘I want this texture, I want this flavour’ and we use that technique to achieve that. What we really pride ourselves on at the restaurant is we don’t want to be at all gimmicky. We don’t want to show off what we know; we just want to provide a good product, so with using techniques and stuff like this, it allows us to do that—but we’re not relying on that.”
So what might you find on your plate if a chef is using some of these practices? It could be something more obvious like spherification, a culinary process that involves shaping liquid into various sizes of spheres that was discovered by the company Unilever in the ’50s and popularized in modernist cuisine by Adrià; various foams and gels that utilize hydrocolloids as thickening agents; vapours; avant-garde presentation style or more subtle, behind-the-scenes techniques such as using liquid nitrogen to make ice cream; using a centrifuge (a machine originally used in labs that spins at high velocity to separates materials by density); or cooking sous vide, a low-temperature process that involves placing an ingredient like meat or beans in a vacuum-sealed plastic bag and into a thermal immersion circulator, where it is cooked at a regulated temperature to produce a consistent doneness.
“Most of our proteins are cooked sous vide,” Staley says. “It allows a texture and a doneness that you just can’t achieve any other way, because, traditionally, if you cook a steak and you cook it on the grill, the outside’s well done and then you’ve got medium and you’ve got your final doneness in the middle, which is medium rare. But if you’re doing a steak sous vide, it’s medium rare from the edge to the middle. You wouldn’t be able to achieve that any other way.”
Kolskog, who has been an instructor at NAIT for 13 years and owned a couple of restaurants prior to that, has also become proficient in sous vide cooking and is currently working on a research project at the University of Alberta in which Alberta-grown pulses like beans and lentils are vacuum sealed and cooked sous vide, but would then be packaged and available to consumers to easily heat up in the microwave. And since the thermal circulator involved in the process will never fluctuate in temperature once it’s set, the technique has proved to be beneficial for students at Ernest’s, NAIT’s on-campus fine-dining establishment.
“One thing you can’t doubt with it is the amazing consistency you get with it,” Kolskog says, noting student turn-around occurs every five weeks and consistent food quality is important within a restaurant setting. “It was probably the greatest tool to achieve consistency for high-end dining.”
The methods are meant to enhance the overall quality and flavour of the food, but there’s still an attractive visual element that comes into play. It’s no longer on the menu, but Staley’s salmon served over white beans became infamous in North 53′s early days for its taste as well as presentation. The dish was served under a glass dome filled with fragrant, effervescent juniper smoke, which would come billowing out as soon as the dome was lifted.
“A lot of people use a PolyScience smoking gun and we use a super aladin—I think it produces a better result,” Staley says. “It’s a silver tubular device and you put whatever you’re smoking in the top and you burn it. It sucks it through a fan and a tube and the fan cools it down, so it’s a cold smoke. Then we put that under the dome and we take it off at the table … Right now we have one [dish] under the dome. It’s chicken that we cook in hay, so you’re burning hay and then when you take it off at the table you smell the burnt hay.”
The smoke is there for more than just showmanship, though. Its flavour is picked up by other elements on the plate, which occurs at different rates depending on the ingredient. Not to mention it involves more of the five senses, creating an all-around dining experience.
“Flavour is a lot more soluble in fat than it is in water, so with the beans in particular and the fat and the cream and the crème fraîche that were in there, they picked up a lot of the smoky flavour.”
Kolskog and his students have experimented with smoking methods as well as liquid nitrogen—a material which allows them to achieve techniques like cryo-shattering fruits and vegetables.
“You can take raw fruits, in some cases raw vegetables, but if you had something like a hard vegetable, like beets, you could roast it, freeze it in the liquid nitrogen until it’s solid and then it shatters like glass,” Kolskog explains. “Let it thaw, but it’s broken into really weird shapes and stuff that you can’t get through any other process.”
A crowd-pleaser at receptions held at Ernest’s continues to be the nitro dragons which, much like the smoke at North 53, are an equal mix of taste and esthetic.
“The one we like to do the most is called the passionfruit bourbon nitro dragon,” Kolskog says. “It’s a little bit of bourbon, passionfruit purée, a little bit of cream, some gelatin, and you put it into a syphon bottle—so it’s bubbly—spray it into a little spoon, put it into the liquid nitrogen, cook it for 15 seconds and present it to the guest. They put it in their mouth and they exhale, and just like a dragon the vapour of the liquid nitrogen comes out.”
In many cases it’s the machinery that makes the difference in whether a chef can execute a certain technique, and Staley’s got one that is unique to North 53—at least for now—called a Pacojet. Staley says it’s turning the process of making ice cream “on its head.” Traditionally, an ice-cream base is mixed together using cream, fruit purée and sugar before going into an ice-cream machine and being frozen, but in the case of the Pacojet, the ice-cream base is put into special beakers that are frozen solid at at least -20C. The beakers are then placed in the machine and a blade designed to spin at 200 rpm comes down on the frozen product and shaves it into incredibly fine pieces.
“Then it injects air into it, which you can either release if you want a more dense texture, or you can leave it so it’s lighter and a bit fluffier,” Staley says. “The only thing comparable is making ice cream with liquid nitrogen, because it gets so fine.”
While techniques stemming from molecular gastronomy—a term chefs often try to steer away from, because it encompasses the scientific study rather than cooking style—appear complicated and, in some cases, unfathomable, Kolskog and Staley maintain the processes are not difficult to grasp. It all boils down to understanding the properties of food, how they react with different agents like hydrocolloids (starch, gelatin, pectin and natural gums) and under various heating methods.
“It’s just your understanding of food properties, especially how things react,” Kolskog says, noting someone could achieve sous vide at home with a vacuum-sealed bag, a large pot of simmering water and a thermometer to keep temperature consistent. “Before I really got into this I never really thought about how food reacts to heat, how food reacts to the addition of moisture to the point that I [do] now. It really gets you thinking and deepens your knowledge and interest of things. You cook meat, it becomes tender, it becomes tasty, but what’s the variance in a degree or two? Is there any at all? All of this comes into play.”
“You’ve just got to understand each hydrocolloid, what it’s properties are,” says Staley, who maintains that modesty is key and these techniques are not meant to be pretentious or inaccessible for diners. “Basically a hydrocolloid is just a gelling agent, but they all just have different properties. Some are more brittle and some are more elastic, some are temperature sensitive, some are thermo-irreversible, so it’s just understanding the wide array that’s available to you.”
The scientific nature of molecular gastronomy and modern cuisine, as well as the machinery and ingredients used, has caused concern that the methods are too chemical or unnatural, but that is not the case. Hydrocolloids and other substances like maltodextrin, enzymes, lecithin, xanthan gum, and transglutaminase (a protein binder), are all derived from natural, edible items.
“All of the additives that we use are naturally derived. So, for example, things like sodium alginate is derived from seaweed, xanthan gum is derived from bacterial fermentation,” Kolskog says. “Calcium chloride they use in cheese processing, [and] agar gum has been around for hundreds and hundreds of years, so a lot of them are naturally derived and you use very small amounts of each.”
“One thing I like to say is, we use soy lecithin in the kitchen … and I go up to someone and say, ‘Have you had bacon bits before? Have you had chocolate before?’ Imitation bacon bits are made with soy lecithin, chocolate is made with soy lecithin. It’s a stabilizer,” Staley explains, noting these types of substances are not chemicals and he considers them tools more than ingredients. “They’re all just different properties of food that, yes, did have to go through a laboratory to be developed and be recognized for what that one ingredient in that thing could achieve, but it’s processed like anything else. It’s processed like salt or it’s processed like gelatin … It’s one of those things that is quite new and I think stuff that is new takes a bit of time to get accepted.”