Researchers at the University of Wisconsin-Madison found that adding polyphenols to ice cream dramatically slows down melting, allowing the frozen dessert to stay solid for hours at room temperature.
“When you have normal ice cream, it will become a puddle of liquid in no time. However, we learned that adding polyphenols to ice cream can create a product that holds its shape for over four hours at room temperature. That’s pretty close to a no-melt ice cream,” Cameron Wicks, a Ph.D. student and researcher at UW-Madison, said.
What are polyphenols and how do they affect ice cream
Polyphenols are naturally occurring antioxidants and anti-inflammatory compounds found in fruits (such as berries, cherries, and apples), vegetables (spinach, carrots, red cabbage, and red onions), seeds (walnuts, almonds, and chia seeds), green tea, black tea, and many spices, including cinnamon and oregano.
These compounds are known to have several health benefits. For instance, they prevent the formation of blood clots, keep blood sugar levels under control, remove harmful gut bacteria, enhance brain functions, and may even block the growth of cancerous cells.
During her research, Wicks noticed that adding polyphenols to ice cream increased its thickness and viscosity. According to Wicks, this occurs because polyphenols interact with the proteins surrounding fat molecules in an ice cream. Several polyphenols bind with peptide molecules and form large protein-polyphenol complexes. This causes the ice cream fat to cluster, resulting in enhanced viscosity and slowed melting.
“Polyphenols create a network between the cream’s fats and proteins that resists the flow of melting ice. In other words, polyphenols help the ice cream hold its shape, leading to fewer drips when left at room temperature,” the researchers note.
Testing the melting rate of ice cream with polyphenols
Wicks and her team performed an interesting experiment during which they compared the melting of regular ice cream with that of ice cream samples containing varying amounts of polyphenols.
They placed each ice cream sample on top of a wire mesh suspended above a beaker at room temperature. The beaker is positioned atop a scale that records changes in the ice cream sample’s weight. Here’s what the researchers found at the end of the experiment:
“Regular ice cream takes around two hours to completely melt and pass through the screen. Whereas polyphenol-rich ice cream can stay on top of the wire mesh for over 4 hours, with only 10% of its total weight dripping through into the beaker during that duration,” Wicks told ZME Science.
They also discovered that polyphenols could keep ice cream smooth and creamy over time by reducing the formation of ice crystals. This property can help maintain the quality of ice cream for longer periods.
However, the researchers didn’t reveal the polyphenol concentration at which they observed these results. They also note that the addition of polyphenols affects a product’s taste, especially since many polyphenols are known for their astringency.
The current experiment did not include a sensory study, so further research is needed to understand the changes polyphenols can alter ice cream’s taste.
Polyphenols are better than traditional stabilizers
Ice cream manufacturers use polysaccharides such as guar gum and carrageenan as stabilizers to maintain the quality and texture of ice cream and increase its shelf life. While these are naturally occurring substances, there has been some controversy regarding their safety, particularly degraded carrageenan.
For instance, in 2015, scientists claimed that carrageenan is highly inflammatory and can lead to several health problems ranging from gut toxicity to rheumatoid arthritis. However, not all researchers agreed with these findings — but it did raise concerns about the use of carrageenan in food items, including ice cream.
“With the shift towards more “natural” products, some consumers may be less inclined to purchase ice creams that contain common polysaccharide gums despite their efficacy in helping to maintain quality,” Wicks added.
In contrast, polyphenols, which are derived from common fruits and vegetables, have many health benefits with no known dangerous side effects. This makes them a health-conscious, approachable alternative to common ice cream stabilizers.
You can read the press release here.
