Once upon a time, a giant candy company sought out ways to improve chocolate manufacturing. The challenge was to reduce chocolate's viscosity, the friction inside liquid chocolate that inhibits its ability to flow without clogging up manufacturing equipment. The company received help from a team of scientists who harnessed the power of electric fields and, in the process, found new ways to make chocolate with less fat and a better taste. And we all lived happily ever after.
It's no fairy tale, though — this really happened. And at no point did a whimsically insane candy maker turn kids into blueberries.
The scientists work at Temple University. They had previously pioneered a method to reduce the viscosity of crude oil by using electric fields, so they built a device to see if a similar approach would work with chocolate.
Essentially, the device consists of a pressurized melting chamber with a tube in the bottom that allows liquid chocolate to flow out. Metal mesh screens in the tube are hooked up to a circuit. The scientists used the screens to generate an electric field in the same direction as the flow of chocolate.
The electric field affected the chocolate's viscosity because chocolate is an electrorheological (ER) suspension. This is a class of liquids containing weakly conductive or nonconductive particles that change dramatically when they encounter an electric field. The changes aren't permanent — remove the field, and the particles return to their normal state.
In the case of chocolate, those particles are cocoa solids. Typically, they are shaped like a ball. It's hard to pack those particles closely together because there's a lot of wasted space. This creates a higher level of viscosity. But when these particles move through an electric field, they change shape and elongate. That means they pack together more snugly, and the liquid is less viscous.
But the researchers realized something else — because the electric field was so effective, they could remove a significant amount of fat from the chocolate without problems. Normally, fat helps keep chocolate flowing. But with the electric field in place, they could remove as much as 20 percent of the fat, depending on the chocolate.
According to the team, some people find the result to be even tastier than normal chocolate. They say that the end product has a more pronounced cocoa flavor than the normally produced versions. It's hard to put a qualitative value on something as subjective as taste. Perhaps they should submit the new chocolate to an ultrasonic scan.
It seems like this is a big win for chocolate lovers out there. Candy companies won't have to worry about their machines clogging up with delicious, viscous chocolate. The chocolate they make can have less fat in it, and it might even taste better. Watch the video above to learn more about the sweet experiment, and pass the hot fudge!