Local brewers have had to change how they make their beer in order to account for the recent shortage in food-grade carbon dioxide.
Local brewers have had to change how they make their beer in order to account for the recent shortage in food-grade carbon dioxide.
Brewers in the Whanganui and Ruapehu regions have had to change the way they produce beer in order to account for the national carbon dioxide shortage.
The brewers had to alter their production schedules as they had around three weeks of gas left in their supplies.
The shortage was causedby the country’s last food-grade liquid CO2 plant at Kāpuni in Taranaki temporarily shutting down due to a safety valve releasing ammonia.
Roots Brewing Co.’s Andy Henshaw said they had enough gas in their supply for around three weeks of production, but they were managing the shortage.
“It’s another speedbump in the road, and every business has gone through some speedbumps over the last few years - this is just one more,” Henshaw said.
“[It’s] not just for carbonating, but for moving beer, for purging vessels ... it’s pretty critical,” he said.
However, the shortage was less of an issue for Roots due to the brewing equipment the company uses.
Roots use unitanks to brew their beer rather than fermenters, which can ferment and carbonate beer in one vessel rather than having to transfer it.
Henshaw said this type of brewing didn’t work for every beer, and it adds around two weeks to the production time, but it significantly decreased their CO2 dependency.
“We can halve our CO2 dependency just by minor process changes.”
To further help, Roots changed its brewing calendar to focus on beers less dependent on gas, and took other measures such as taking away their tasting tap.
Ruapehu Brewing Co. founder Austin Hobson said the shortage had caused the company to strategise what beer they produce as well.
“At the moment our supply’s been fine, but in a week, in the next week, and the following week, when I’ve got a lot of packaging to do, I’ve got to be careful,” he said.
Producing beer for cans required much more CO2 than producing beer for kegs, Hobson said.
The cans are open vessels while they are being filled, which means it’s much easier for oxygen to get into the beer.
“Beer doesn’t like oxygen, essentially, so we package under a blanket of CO2 within the can, and also before it gets the lid put on the top, it’s in a tunnel that basically has carbon dioxide purging into it to push any oxygen out of there,” he said.
If they didn’t do this while canning the beer, he said there was a chance of the beer oxidising, which would make it taste “a bit like wet cardboard”.
Kegs, on the other hand, are already purged before being filled with beer, so less CO2 is required.
Because of that, Hobson said they’ve had to be careful with which products they make, whereas previously they would package any beer that was ready.
“You have to be really careful because - do you package more beer? [Because] then you have to hold off on carbonating the beer and let it sit in a tank and wait until you’ve got more supply. So, it’s a bit of a juggling act at the moment.”
The shortage was especially affecting small brewers like his as they were at the bottom of the food chain for gas distributors, he said.
“If the gas taps don’t get turned back on, in two or three weeks’ time the story will be a lot different because we’ll probably run out by then.”
The shortage had also led to the price of CO2 skyrocketing, which he said would eventually be felt by someone, whether it’s the producers or the consumers.
Over the last week, Henshaw said the price of the gas Roots used increased by 70 per cent per kilogram.
The owner of the Kāpuni plant, Todd Energy, said liquid CO2 production is expected to restart early next month, but initially at a 30 per cent production capacity.
