Science & Technology - Posted by Anna Blackaby-Warwick on Monday, August 13, 2012 11:31 - 7 Comments
Fruit juice cuts chocolate’s fat in half
U. WARWICK (UK) — Soon, chocolate bars could have up to 50 percent less fat, thanks to fruit juice and chemistry.
Chemists at the University of Warwick have taken out much of the cocoa butter and milk fats that go into chocolate bars, substituting them with tiny droplets of juice measuring under 30 microns in diameter.
They infused orange and cranberry juice into milk, dark, and white chocolate using what is known as a Pickering emulsion.
Crucially, the clever chemistry does not take away the chocolaty “mouth-feel” given by the fatty ingredients.
This is because the new technique maintains the prized Polymorph V content—the substance in the crystal structure of the fat that gives the chocolate its glossy appearance, firm and snappy texture, but also allows it to melt smoothly in the mouth.
Stefan Bon says the research looks at the chemistry behind reducing fat in chocolate, but now it is up to the food industry to use this new technique to develop tasty ways to use it in chocolate. (Credit: University of Warwick)
Straight from the Source
The final product will taste fruity—but it’s also possible to use water and a small amount of ascorbic acid (vitamin C) instead of juice to maintain a chocolaty taste.
Stefan Bon from the department of chemistry is lead author of the study published in the Journal of Materials Chemistry.
He says the research looks at the chemistry behind reducing fat in chocolate, but now it is up to the food industry to use this new technique to develop tasty ways to use it in chocolate.
Bon says: “Everyone loves chocolate—but unfortunately we all know that many chocolate bars are high in fat.
“However it’s the fat that gives chocolate all the indulgent sensations that people crave—the silky smooth texture and the way it melts in the mouth but still has a ‘snap’ to it when you break it with your hand.
“We’ve found a way to maintain all of those things that make chocolate ‘chocolaty’ but with fruit juice instead of fat.
“Our study is just the starting point to healthier chocolate—we’ve established the chemistry behind this new technique but now we’re hoping the food industry will take our method to make tasty, lower-fat chocolate bars.”
The scientists used food-approved ingredients to create a Pickering emulsion, which prevents the small droplets from merging with each other.
Moreover, their chocolate formulations in the molten state showed a yield stress, which means that they could prevent the droplets from sinking to the bottom.
The new process also prevents the unsightly “sugar bloom” which can appear on chocolate which has been stored for too long.
The study is co-authored by Thomas Skelhon, Adam Morgan, and Nadia Grossiord at the University of Warwick.
More news from University of Warwick: http://www2.warwick.ac.uk/newsandevents/