Chewing the fat with a food scientist

Ever wondered what causes that greyish coating on chocolate?

Food scientist and professor Dérick Rousseau knows–he’s studied it at Ryerson University, in Toronto, where he leads a food research laboratory. Beyond working with confectionery companies on how to reduce the offputting grey coating (called “fat bloom”) to extend the shelf life of chocolate, Rousseau is also exploring how to cut back on the use of synthetic emulsifiers in foods.

Canadian Grocer managing editor, Alicia Androich, spoke with Rousseau about his fascinating research, the misconceptions about shelf life and what’s on foodmakers’ radars today.

YOU’RE FAMOUS FOR YOUR RESEARCH ON CHOCOLATE. WHAT’S YOUR MAIN FOCUS IN THAT AREA?
About three-quarters of it has been on how to extend the shelf
life of chocolate by reducing fat bloom. You see fat bloom on older chocolate or chocolate that’s been “temperature cycled” inadvertently. Say you purchase a chocolate bar in an air-conditioned shop on a hot day.

You go outside or leave it on the dashboard, and it almost melts. You get home and put it in the fridge, then later on the counter. Those temperature fluctuations will greatly accelerate the onset of fat bloom.

People think, Oh my God, the chocolate’s gone mouldy. But it’s simply a visual defect; it’s completely fine to eat.

WHAT OTHER RESEARCH DO YOU DO?
I look at shelf life and stability of processed foods. We do a lot of work with products that can exist as gels. There’s also a big push in my lab right now on emulsions–things like vinaigrettes or table spreads–and trying to understand how those products can have long-term shelf stability.

I also work on approaches to reduce the use of synthetic emulsifiers. More food companies are looking at clean label declarations. You might see something like polysorbate 80 on an ingredient label. That emulsifier has a very specific application. How, then, can you find a natural equivalent that will avoid the use of this emulsifier?

WHAT ARE SOME OF THE MISCONCEPTIONS WE HAVE ABOUT SHELF LIFE?
With fluid milk that you purchase at the grocery store, consumers will look at the best before date and presume it will stay good, at the very least, until that date. Well, that’s if the milk isn’t opened. Once you open that carton there is the possibility the milk will go sour prior to the best before date.

Often the best before dates aren’t really critical.

Yogurt is often fine after its best before date if it’s unopened; I’ve had yogurt that’s three weeks past that date, no problem. I love Sriracha sauce, but don’t consume it much. I have a bottle that is well beyond its best before date.

IS REDUCING SALT IN PROCESSED FOODS STILL AS BIG FOR FOODMAKERS AS A FEW YEARS AGO?
It’s kind of dying out right now. For better or worse, a possible reason is that it’s very difficult to reduce salt in foods. It’s plentiful, it’s cheap, but what people or processors don’t necessarily realize is it also helps with the microbiological safety of the food. It helps to prevent growth of certain microbes, and it also has a really important functional role. For example, if you ever try to make bread and don’t add salt, you’re going to have a loaf that will not have a very nice texture.

WHICH BIG FOOD TRENDS ARE YOU SEEING IN THE FOOD INDUSTRY TODAY?
There’s a current push on protein. A lot of foods are enriched in protein and this is, in part, related to the push toward satiety–the feeling of fullness. There’s a perception that protein can help you with body weight management.

There’s also a push toward sugar reduction.

HOW DOES YOUR INTEREST IN FOOD TRANSLATE INTO YOUR PERSONAL LIFE?
I enjoy cooking a lot. I cooked for my own wedding. When I was very young, I would look at the ingredients on a cereal box and say to my mother, “We have all the ingredients to make cereal, so why don’t we make it ourselves?”

INSIDE OR OUTSIDE THE LAB, WHAT’S THE MOST UNUSUAL FOOD YOU’VE EVER TRIED?
Live octopus. I was in Korea. They chop it up and it’s still moving; I was told to eat it quickly or else the suckers would latch onto the inside of my mouth.

WOULD YOU TRY THAT AGAIN?
Nope.