There could be a shortage of beer and fizzy drinks in the US as supplies of carbon dioxide from ethanol plants run low.
Brewers and soft drink manufacturers use CO2 for carbonation – making drinks fizzy.
Ethanol producers capture CO2 as a byproduct and sell it to the food industry in large quantities.
But ethanol production – which is blended into the nation’s fuel supply – has fallen sharply due to the drop in petrol demand as a result of lockdown measures during the coronavirus pandemic.
Petrol demand is down by more than 30% in the US, and the dwindling ethanol output is affecting the food industry as a result.
Renewable Fuels Association chief executive Geoff Cooper said that 34 of the 45 US ethanol plants that sell CO2 have idled or cut production.
And CO2 suppliers have increased prices by around 25% due to reduced supply, according to Brewers Association chief executive Bob Pease.
The trade group represents small and independent US craft brewers, who get about 45% of their CO2 from ethanol producers.
Mr Pease added: “The problem is accelerating. Every day we’re hearing from more of our members about this.”
He expects brewers will start cutting production in two to three weeks.
In a letter to Vice President Mike Pence on 7 April, the Compressed Gas Association (CGA) said production of CO2 had fallen by about 20%.
It added that it could be down by 50% by mid-April without relief.
Meat producers are also being affected as they use CO2 in processing, packaging, preservation and shipment.
For some Americans, the COVID-19 lockdown has already had an impact on beer supplies.
Olive Veronesi, a 93-year-old from Pennsylvania, recently went viral after a photo of her holding a sign that said “I NEED MORE BEER!!” was posted on Facebook.
The company that makes her favourite brand has now delivered 150 cans to her door.
Orion Melehan, chief executive of beverage company Life-AID in California, said two of his production partners are looking for alternative CO2 sources.
“It does have us up at night figuring out what our options are,” Mr Melehan said. “It highlights the laws of unintended consequences.”
A spokeswoman for National Beverage Corp said the company sources from a number of national CO2 suppliers and does not anticipate a supply issue.
The Coca-Cola Company, SodaStream owner PepsiCo Inc, wine and beer seller Constellation Brands Inc and several bottling companies have not publicly commented on whether they will be affected by the shortage.
However, Denmark-based Carlsberg Group said that the company is “almost self-sufficient”.
“We, in line with our sustainability program, create our own CO2 and capture it during the brewing process,” spokesman Kasper Elbjorn said.