What is CO2? How Carbon Dioxide is produced, what it’s used for in food industry - and why there’s a shortage

CO2 is primarily used in food packaging and as a method of stunning animals prior to slaughter, but its uses are many and varied

A shortage of carbon dioxide (CO2) has developed after production was paused at two fertiliser factories in northern England last week, which supply 60% of Britain’s CO2.

US firm CF Industries, which owns the factories, blamed rising gas prices for making its operations unviable.

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The UK Government has since announced it has struck a deal with CF Industries to provide financial support to restart the plant.

Environment Secretary George Eustice said the Government would support CF “just for a few weeks” at a cost of “possibly tens of millions” of pounds.

But what is CO2 used for, and how is it produced?

Here is everything you need to know about it.

What is CO2 used for in the food industry?

The gas is used primarily in food packaging and as a method of stunning animals prior to slaughter, but its uses are many and varied and largely essential.

Talking on Sky News, Nick Allen, chief executive of the British Meat Processors Association, said: “The meat industry, in particular the pig and poultry industry, use CO2 for humane slaughter. 80% of pigs and poultry are slaughtered using that process.”

While sheep and cattle are still mostly killed using a captive-bolt stun pistol, pigs and poultry are now more often stunned with high concentrations of CO2, resulting in gradual loss of consciousness before they go to slaughter.

Allen said meat manufacturers have said they have between five and 15 days’ supply left, but then “they will have to stop”.

“That means animals will have to stay on farms. That will cause farmers huge animal welfare problems and British pork and poultry will stay off the shelves. We’re two weeks away from seeing some real impact on the shelves.”

CO2 is not only used for the humane slaughter of livestock, it also extends the shelf-life of products and is vital to cooling systems for refrigeration purposes.

CO2 is injected into the packaging of perishable foods such as meat and salads to inhibit the growth of bacteria. It typically prolongs the shelf life of products such as beef steak by around five days.

In baked goods, such as bread and pastries, and some cheeses, it is used at concentrations of up to 100% to deter mould.

CO2 is also widely used in fizzy drinks and beer and is also vital to cooling systems used to refrigerate products. It is also used to create dry ice, which can be used to keep food fresh for storage and transport.

It is also used in the UK in industrial glasshouses to encourage strong growth and can be used to purify drinking water.

How is it produced?

A view of CF Industries’ fertiliser plant in Stockton-on-Tees, northeast England (Photo: PAUL ELLIS/AFP via Getty Images)

The problem has been caused by the shutting down of two large fertiliser plants in Teesside and Cheshire – which produce CO2 as a by-product – with the owners citing the hike in gas prices as their reason for closing.

Wholesale prices for gas have surged 250% since January – with a 70% rise since August alone, leading to calls for support from the industry.

The shutdown of CF Fertilisers’ plants coincided with maintenance at two other factories which supply CO2 to the UK.

“Those plants closed, and they account for about 60% of the CO2 produced in this country,” said Allen. “They closed at very short notice with no warning. It really hit us cold.

“We’re hoping and praying the Government can negotiate with these plants to reopen. But even then, it’ll take about three days to restart.”

Will the Government’s deal work?

The deal with CF Industries will be in place for three weeks while the “CO2 market adapts” to the surge in global gas prices, according to the Department for Business, Energy and Industrial Strategy (Beis).

Environment, Food and Rural Affairs Secretary George Eustice said the final details of the agreement were still being worked on but “it’s going to be into many millions, possibly the tens of millions”.

Ian Wright, chief executive of the UK’s Food and Drink Federation, welcomed the deal and said product shortages would not be as bad as previously feared if production can restart at “appropriate scale” before the end of the week.

He added: “When we are certain that the immediate supply issues are resolved, we should then work with Government to build resilience into the production of CO2 to protect our food supply chain.”

Beis officials said the “exceptional short-term arrangement” with the American business would allow the company to immediately restart operations and produce CO2 at its Billingham plant in Teesside.

Eustice suggested the second plant would also be brought back online.

He said the food industry will have to accept a major hike in C02 rates, which could increase fivefold from £200 a tonne to £1,000, but because the gas makes up only a small part of overall costs there would not be a “major impact on food prices” for consumers.

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