The project, entitled ProCardo, aims to help producers “get more out of cardosins”, enzymes that function as a vegetable coagulant (“rennet”) and that give the cheese its unique characteristics, FCUP said in a statement.

These enzymes are present in the thistle flower, which is found in the interior of the country from Serra da Estrela to the Algarve.

Generally, the flowers used in the production of Serra da Estrela Cheese come from the south of the country, an area susceptible to the effects of drought and excessive heat "in a growing trend" due to climate change.

In this sense, the researchers want to understand whether climate change could threaten the quality of these cheeses and provide the cheese industry with tools to "overcome possible changes in the characteristics of cardosins in thistle flowers."

Quoted in the statement, the project leader, Cláudia Pereira, clarifies that there are two types of important cardosins in the vegetable coagulant (A and B) with different properties in their action: cutting the main milk protein [casein] and promoting its coagulation.

"We know that the proportion between cardosin A and B is very important for the cheese to maintain its characteristics", highlights the researcher from FCUP and GreenUPorto – Research Center for Sustainable Agrifood Production.

At the moment, the team is carrying out field tests in Viseu in situations of 'stress' and water comfort and comparing the results with tests carried out on plants in Beja, Alentejo, where in greenhouses they are subject to high temperatures.

The objective is to understand how the expression of these enzymes varies when exposed to different types of environmental stress, and the first field tests made it possible to understand that there are differences in the proportion of cardosins produced in plants exposed to high temperatures and those produced in plants in a situation of water comfort.

"Normally in thistle flowers, we have a greater amount of cardosin A than cardosin B, but in plants exposed to higher temperatures the proportions tend to equalise", says the researcher.

Depending on the field trials, the researchers intend, in the future, to select some of the most extreme conditions, obtain flowers harvested in these conditions and use them in the production of Queijo da Serra da Estrela PDO.

"This cheese will be analysed in relation to its physical-chemical characteristics in the laboratory and by the Serra da Estrela PDO Cheese tasting chamber panel, for sensory evaluation regarding texture, flavor and aroma", adds Cláudia Pereira.

As part of the project, which has funding of 150 thousand euros from the Promove program, an initiative of BPI, the "La Caixa" Foundation and the Foundation for Science and Technology (FCT), workshops are also planned to be held to showcase and present the results of the project to the cheese industry.

The project runs until 2026 and has as partners the Polytechnic Institute of Viseu, the Agricultural and Agro-Food Biotechnology Center of Alentejo (CEBAL), in Beja, and the Queijaria de São Cosme, in Gouveia. Collaboration with Spanish producers who will be able to access and benefit from the scientific knowledge produced is also planned.