Running out of fizz: CO2 shortage in NZ

New Zealand is reported to be facing a shortage in carbon dioxide for use in food processing. The shortage is driven by a reduction in local production capacity, which could impact the availability and prices of sparkling wine, ready-to-eat meals, meats and carbonated drinks.

CO₂ is used in food manufacturing in a variety of ways. It acts as a preservative for foods like meat and chips because it can kill some of the microorganisms; it provides the fizz to carbonated soft drinks and alcohols; it is even used in the meat industry for stunning animals before they are slaughtered. While the atmosphere is warming due to the presence of CO₂, it is difficult to extract the relatively small percentage of the gas found in air. Shortages mean that some foods and beverages may not be able to be produced whereas others will have to be sold to consumers at higher prices.

Last year the United Kingdom faced similar shortages. This was caused by a swirl of circumstances but it was primarily due to reduced fertiliser production, which is how the country sourced much of its CO₂. Deals were cut to avoid this problem but dire predictions were made for Christmas dinners without turkey or other commonly used foods.

The food-grade CO₂ shortage in New Zealand is partly driven by the March closure of the country’s Marsden Point oil refinery which produced CO₂ as a by-product of its operations. Subsequently the only domestic source of liquid and food-grade CO₂ is a plant at Todd Energy’s Kapuni gas field in Taranaki.

The reduced amount of CO₂ being produced in the country has resulted in some companies receiving half the usual amount of CO₂, with their existing stocks of the chemicals gradually depleting and not being refilled.

One solution that could be considered to address the problem is a technology that CSIRO has produced called Airthena, which is able to draw carbon dioxide from the air for use in carbonated drinks but it may not be widely available yet.

Image credit: iStock.com/Mihail Minin