GAZTANOLA, obtaining scientific evidence applicable to the process for requesting the use of wooden shelves in the Basque Country

GAZTANOLA, obtaining scientific evidence applicable to the process for requesting the use of wooden shelves in the Basque Country

Wooden shelves play a fundamental role in cheese ripening, as this traditional material gives unique sensory characteristics to the product, granting it a distinctive typicity. This typicity refers to the set of unique attributes that differentiate a cheese on the market.

After the production, cheeses must undergo a ripening stage to develop their organoleptic characteristics. During this period, the cheese is exposed to specific environmental conditions and care which, depending on these factors, will result in a distinct sensory profile for each of its attributes.

Wood offers many advantages in the cheese ripening process. It plays a very important role in humidity regulation, the boards absorb excess moisture and release it when there is not enough. In addition, wood brings other important advantages during cheese ripening, due to the formation of protective biofilm on the surface of the shelves. This biofilm is composed of harmless microbial flora which is responsible for the development of sensory attributes such as texture, flavour and aromatic profile. In addition, several scientific studies have demonstrated the safety of wooden shelves against Listeria monocytogenes. The resident microbial biofilm in the ripening wood inhibits the growth of this pathogenic bacterium. On the other hand, it has been demonstrated that the cleaning treatments used for sanitizing wooden shelves through the application of thermal treatments, are effective against the possible presence of Listeria monocytogenes if it were to develop.

The dairy sector in the Basque Country is undergoing a growing evolution, both the number of new cheese dairies and the number of cheese types marketed. Cheesemakers are aim to innovate and diversify their offering to provide new products to their customers and thus improve their market competitiveness. The wooden shelves used in the cheese ripening process play an critical role in this contest.

Hygienic-sanitary regulations

Hygienic-sanitary regulations govern the use of traditional materials, such as wooden shelves, for cheese ripening in dairies. In Spain, AESAN, the Spanish Agency for Food Safety and Nutrition, allows their use in all Autonomous Communities and has published a ‘Guidance document on derogations for foods with traditional characteristics in the framework of Regulation (EC) No 2074/2005’. However, it is the competence of each Autonomous Community to manage the process exception requests by the cheese dairies, to assess them and to grant or deny permission. The Basque health authorities request, on the one hand, proof that the cheese intended to be ripened on wooden shelves is a food with traditional characteristics (with a history of at least 30 years in the Member State) and, on the other hand, proof that wood provides some benefit on the cheese compared to other materials.

Gaztanola project

At Dairy Centre- Leartiker, as a reference centre that working to address the needs of the Basque dairy sector, we see the need to facilitate the process of applying for an exception to the use of wooden shelves by Basque dairies, Thus, in October 2023 we launched the GAZTANOLA project funded by the Basque Government’s Berriker program, which supports research, development and innovation in the agricultural, forestry, fisheries and aquaculture sectors. The aim of the GAZTANOLA project was to generate scientific results that can be used by the Basque Health Authorities in the process of granting exceptions for the use of wooden shelves, so that their suitability and necessity were well-argued, demonstrated and justified, enabling the generation of required documentation by the Basque Department of Public Health. The project has been developed in collaboration with different agents in the sector, such as, Elika Fundazioa, HAZI Fundazioa, EEE (Esnekigileen Euskal Elkartea), QueRed (Network of Artisan and Country Cheese Dairies) and two cheese dairies that produce hard and blue cheeses.

The research activities, including bibliographic analysis, microbiological research and application of the sensory analysis methodology have focused on two categories of cheese, hard cheeses and blue cheeses.

The aim of the bibliographic analysis was to obtain evidence to show that both hard and blue cheeses made in Basque cheese dairies are foods with traditional characteristics. In order to demonstrate that the use of wooden shelves in cheese ripening does not compromise the product’s food safety (compared to other materials), and that it can even offer a microbiological benefit due to the biofilm formation, microbiological research have been carried out. These experimental activities have been carried out at the Dairy Centre facilities, where different batches of both hard and blue cheeses were produced, as well as on two cheese dairies.

The cheeses were ripened under identical environmental conditions using different materials, such as wooden shelves, mats placed on metal grills and plastic boxes. Thus, microbiological controls (pathogens, hygiene indicators and harmless lactic flora) were performed both on the cheeses and on the ripening surfaces and physicochemical controls (pH, aW, salt) on the cheeses throughout the ripening process.

The experimental cheeses ripened on the different materials (wood, mat and box), were subjected to sensory analysis at the end of their ripening period in order to determine whether the use of wood imparted distinctive organoleptic characteristics to cheese.

The work described above was carried out over 15 months, obtaining the following results:

Traditionality: A document was developed that demonstrates and justifies the traditionality of both hard and blue cheese in the Member State.

Benefits of wooded shelves: It has been demonstrated that the use of wooden shelves in the ripening of cheese has several benefits:

– Improved yield: Wood acts as a moisture regulator. Less weight loss has been observed in hard cheeses ripened on wooden shelves, compared to those matured on mats and boxes.

– Development of harmless microbial flora: Evidence showed more abundant development of harmless flora (mesophilic aerobic flora, molds and yeasts) on the surface of the wooden shelves used mainly in hard cheeses ripening, compared to surfaces of mats and boxes, which has a direct influence on the sensory characteristics of the cheeses. The results obtained in the microbiological analyses carried out in the field dairies, were comparable to or exceeded the microbial counts observed in experimental trials.

– Differentiated sensory characteristics: evidence has been obtained that the material used in the cheese ripening process has a direct influence on the sensory characteristics developed in each type of cheese, thus giving it typicity and helping to differentiate it.

Safety of the wooden shelves: Listeria monocytogenes was not detected in any of the samples analyzed (work surfaces or cheeses) during either the experimental tests or in the analyses carried out in the two dairies. We can therefore affirm that the wooden shelves are safe for the ripening process of hard and blue cheeses and can guarantee the food safety of the product.

The results generated in the GAZTANOLA project will be transferred to the sector with the aim of making them applicable in the processes of requesting an exception for the use of wooden shelves in the ripening of their cheeses in the Basque Country.