Resilience in Retrospective: The Trajectory of Agro-Pastoral Systems in the Centro Region of Portugal

Agro-pastoral systems in southern European regions have been subjected to various disturbances in the past few decades. Still, a certain amount of resilience allowed to withstand its sharp decline. The Serra da Estrela cheese production, the most representative agro-pastoral system of the Portuguese Centro Region, is a demonstrative case study. The main objective of this research is to understand the trajectory of this system up to present, its adaptation to internal and external changes and evolution trends. We used the concepts of resilience and socio–ecological system as framework in a qualitative study. Participatory methods were applied using the perspectives of local actors, in order to identify and analyze the key factors. The main drivers are socio-demographic (ageing, depopulation, social perception of the profession), economic (free market, industrialization), political (lack of adequate of national and European policies) and environmental (climate change, forest fires). Our results are in line with other European cases. To cope with these trends, the system is irreversibly transforming, moving into a new trajectory characterized by different systemic architecture. In face of the ongoing changes, the interactions between the social and the ecological subsystems are blurring, whereas local communities and traditions are being excluded.

Production of Serra da Estrela cheese from ultrafiltered sheep’s milk

The objective of this study is to elaborate Serra da Estrela cheese with sheep's milk concentrate by ultrafiltration and characterize it in relation to protein, yield, proteolysis, amino acid profile, and acceptability. The cheese elaborated with concentrate milk (F2) presented an increase of 17% yield, and protein content was 2 times higher than cheese without concentrate milk (F1). On the 30thday of storage F2 presented an increase of the amino acids and also of proteolysis extension and depth index in relation to the 1st day. Also presented better sensorial characteristic in relation to F1. Were observed positive correlations (>0.85) between acceptability in relation to protein, depth index, extensionand extension index, valine, methionine, serine, phenylalanine aspartic acid, valine andproline. Cheese elaborated with concentrate milk and coagulated with thistle flower is one alternative to increase cheese yield with differential sensorial characteristics.

Influence of Cardoon Flower (Cynara cardunculus L.) and Flock Lactation Stage in PDO Serra da Estrela Cheese

Serra da Estrela (SE) cheese is one of the most appreciated Portuguese cheeses, being produced only from raw ewe’s milk, cardoon flower and salt. Cardoon takes part in two important processes in cheese production—coagulation and proteolysis—contributing to its unique features. Furthermore, milk chemical characteristics change during the milking season, being another factor that account for the high variability of cheese attributes. Therefore, the purpose of this work is to study the influence of cardoon flower (commercial, 6 M and 3 M) and flock lactation stage (November 2018, February and April 2019) in the final characteristics of SE cheese. The parameters analysed were moisture, protein, fat and salt contents, texture and colour. Results showed that flock lactation stage has the highest influence in all the studied characteristics, corresponding the early stages of lactation to the most protein-rich and low-fat cheeses. Cardoon flower affects mainly fat and rind colour. This study allows us to conclude that seasonal changes in ewe’s milk have a considerable impact in cheese attributes, and that although cardoon type had a more restrained effect, when used with expertise it may help adjust cheese sensory characteristics in order to obtain a final product that matches consumer acceptability requirements.

Evaluation of texture of cheese by-products incorporated bread

This work aimed to develop new breads incorporating whey residue, “sorelho”, obtained from ewe’s milk after the production of Serra da Estrela Cheese. For this, we baked three types of bread: wheat bread (control sample), bread incorporating sorelho, and another version containing additional nutritional elements. The texture was evaluated with a texturometer, using compression and perforation tests. Results showed that sorelho can be successfully incorporated in bread. The best product was the bread with sorelho plus improved nutrition, which presented good textural characteristics during a period of 24 hours. This trend was observed for all properties evaluated: hardness, chewiness, resilience, cohesiveness, springiness (compression test) and external firmness, inner firmness, stickiness, adhesiveness (perforation test). Finally, factor analysis showed: FACTOR 1 – compression textural properties; FACTOR 2 – perforation firmness properties and FACTOR 3 – perforation adhering properties, which in total explained approximately 81% of total variance.

Evaluation of texture in Serra da Estrela cheese manufactured in different dairies

Serra da Estrela cheese is a traditional product from artisanal manufacture using raw ewe’s milk coagulated with dried, wild thistle flower. The present study aimed to investigate the variation of textural properties in Serra da Estrela cheeses manufactured in different dairies through time, namely from April to June, following the end of the cheese making season. Three types of tests were conducted: compression, puncture and spreadability. These were carried out on samples coming from six different dairies situated in the PDO (Protected Designation of Origin) region of this type of cheese.The results obtained showed some non-negligible differences for some textural properties between the top and bottom sides of the cheeses evaluated, as well as between cheeses from different dairies. Nevertheless, the properties of springiness, resilience, cohesiveness and adhesiveness (all from the compression test), were not significantly different in the samples analysed. In what concerns the variations along the milking season, it was possible to conclude that three of the considered dairies produced cheeses with a more constant textural profile in the period comprised between April and June. Furthermore, statistical analysis revealed that the correlations between the textural properties were strong for some interactions between properties form the same test and/or from similar nature.