Mar 22, 2022 06:11 AM
https://cosmosmagazine.com/science/chemi...cellulose/
EXCERPTS: What’s worse to eat than a crunchy, icy bite of ice cream? Chemists have figured out how to ensure the ice cream stays soft – using a type of cellulose taken from plants. They say their discovery could also be used to preserve other frozen foods as well, and perhaps even organ and tissue donations.
The reason ice cream sometimes picks up its criminal crunch is the ‘ice’ part. All ice cream has tiny ice crystals in it. If these crystals are very small – less than roughly 50 micrometres, or the width of a human hair – they’re not noticeable. But the larger they get, the grainier and crunchier the food becomes.
Manufacturers avoid big crystals by freezing their ice cream very quickly at very low temperatures (often with liquid nitrogen), and with lots of mechanical agitation. But if the ice cream melts and re-freezes while being transported or stored, this good work is lost.
“Controlling the formation and growth of ice crystals is thus the key to obtaining high-quality frozen foods,” says Dr Tao Wu, a researcher in the Department of Food Science at the University of Tennessee, US.
Wu and colleagues looked to nature for an additive that prevents these large crystals, regardless of how the ice cream is frozen. [...] Cellulose nanocrystals aren’t toxic, but they’d need to be reviewed by food safety authorities before being added to ice cream. Nevertheless, Wu is excited by their potential... (MORE - missing details)
EXCERPTS: What’s worse to eat than a crunchy, icy bite of ice cream? Chemists have figured out how to ensure the ice cream stays soft – using a type of cellulose taken from plants. They say their discovery could also be used to preserve other frozen foods as well, and perhaps even organ and tissue donations.
The reason ice cream sometimes picks up its criminal crunch is the ‘ice’ part. All ice cream has tiny ice crystals in it. If these crystals are very small – less than roughly 50 micrometres, or the width of a human hair – they’re not noticeable. But the larger they get, the grainier and crunchier the food becomes.
Manufacturers avoid big crystals by freezing their ice cream very quickly at very low temperatures (often with liquid nitrogen), and with lots of mechanical agitation. But if the ice cream melts and re-freezes while being transported or stored, this good work is lost.
“Controlling the formation and growth of ice crystals is thus the key to obtaining high-quality frozen foods,” says Dr Tao Wu, a researcher in the Department of Food Science at the University of Tennessee, US.
Wu and colleagues looked to nature for an additive that prevents these large crystals, regardless of how the ice cream is frozen. [...] Cellulose nanocrystals aren’t toxic, but they’d need to be reviewed by food safety authorities before being added to ice cream. Nevertheless, Wu is excited by their potential... (MORE - missing details)