While conventional freezers are incredibly useful at prolonging the life of our food, they tend to consume a lot of energy. An alternative technology, however, promises to solve that issue, while also improving overall food quality.
The process is called isochoric freezing, and its original purpose was to cryopreserve tissues and organs for transplants. More recently though, scientists have started exploring how it could be widely adopted for food storage, and a new study shows that adopting this process on a large scale could generate huge energy savings.
The original idea behind isochoric freezing was to improve the viability of tissues and organs for transplantation by preventing the formation of harmful ice crystals — something that often happens in conventional freezers — which damages the biological materials and can render them no longer useful.
As reported by New Atlas, conventional freezing techniques rely on exposing objects to the air and temperature of 0 °C (32 °F), which freezes them solid. By contrast, isochoric freezing involves placing the object in a closed chamber, typically made of hard plastic or metal, and immersing in in liquid inside. As the chamber is cooled down to a preset temperature, the liquid protects the object inside from forming ice crystals, thus better preserving its qualities.
“Energy savings come from not having to freeze foods completely solid, which uses a huge amount of energy, plus there is no need to resort to energy-intensive cold storage protocols such as quick freezing to avoid ice crystal formation,” said study author Cristina Bilbao-Sainz.
The novel new study, carried out by Boris Rubinsky, who invented the process, together with Bilbao-Sainz and scientists at the US Department of Agriculture, found that integrating isochoric freezing within the global food chain could save massive amounts of energy while also improving the quality of such foods like tomatoes, potatoes, and leafy greens during preservation.
“A complete change over to this new method of food freezing worldwide could cut energy use by as much as 6.5 billion kilowatt-hours each year while reducing the carbon emissions that go along with generating that power by 4.6 billion kg (10.1 billion lb), the equivalent of removing roughly one million cars from roads,” said Bilbao-Sainz.
“These savings could be achieved without requiring any significant changes in current frozen food manufacturing equipment and infrastructure, if food manufacturers adopt this concept,” she added.
What’s particularly enticing about scaling up the process is the fact that the equipment need for isochoric freezing is neither complicated nor too expansive. What’s more, these specialized chambers could be placed in conventional freezers in industrial settings or even homes.
Study source: Renewable and Sustainable Energy Reviews — Analysis of global energy savings in the frozen food industry made possible by transitioning from conventional isobaric freezing to isochoric freezing