It is often called the Ferrari of Italian cheese, but even Parmigiano Reggiano is struggling to stay cool in a warming climate.

Inside warehouses in northern Italy, hundreds of thousands of wheels are slowly aging, gaining both flavor and financial value. Known as "cheese banks," these facilities store the prized wheels, which can also be used as collateral to help producers secure financing.

"Here we have 300,000 forms and another 200,000 in another facility, so 500,000 wheels with a value above 300 million euros [$346m]," says Giancarlo Ravanetti, General Manager of Magazzini Generali delle Tagliate.

Time is crucial to the cheese's value. Parmigiano Reggiano must be aged for at least 12 months, while each wheel is carefully monitored and tested. Before being certified as Parmigiano Reggiano, each receives a seal of approval and is tracked by age and origin.

But increasingly extreme temperatures are adding to the cost of that process. Italy has experienced its hottest summer since 1950, putting pressure on warehouses that must maintain carefully controlled temperature and humidity levels.

"We've had significant costs, a sharp increase in electricity consumption between 25 and 30% compared to last year," Ravanetti tells CGTN.

Pressure throughout the chain 

The pressure starts even earlier in the supply chain, on the farms that produce the milk. Heat stress can cause dairy cows to eat less and produce less milk. For Parmigiano Reggiano producers, that can mean a significant reduction in output.

"The first loss is the milk loss – production losses range from 10 to 20%, depending on the conditions of the farm," Giovanni Buonaiuto, Head of the Primary Production Service at the Parmigiano Reggiano Consortium, tells CGTN.

Producers also face geographical constraints. Parmigiano Reggiano has Protected Designation of Origin status, meaning the cheese can only be produced within a defined area of northern Italy.

Nicola Bertinelli, President of the Parmigiano Reggiano Consortium and a dairy farmer whose family farm dates back to 1895, says the industry needs greater support from regional, national and European authorities.

"In the short term, Parmigiano Reggiano is not at risk, but we are really concerned about the medium and long term," Bertinelli tells CGTN.

Adapting to survive 

Farmers are responding by investing in cooling systems and water tanks to help cattle cope with higher temperatures. Renewable energy is also increasingly seen as a way to reduce exposure to rising electricity costs.

"We have to adapt, we have to manage all the variables to keep the production here," says Bertinelli.

For now, higher costs have not translated into higher prices for consumers. But with heat squeezing the industry from both ends, from the cows producing the milk to the warehouses storing the cheese, that could change.

And when hundreds of thousands of aging wheels also serve as collateral, the stakes extend far beyond the barn, all the way to the bank.