Impact of environmental conditions on the ripening of Queijo de Évora PDO cheese.

"Queijo de Évora" is a traditional Portuguese cheese from raw ewe's milk and granted with PDO label. It is ripened traditionally in rooms with empirical control of temperature and humidity. Nowadays, almost all cheese factories use rooms with temperature and humidity control, but still a significant heterogeneity among cheeses is acknowledged due to unequal distribution of environmental conditions. This paper discusses the influence of the environmental conditions on the ripening of Queijo de Évora, including the application of computational fluid dynamics in steady state conditions. Experimental data was obtained in cheeses ripened along the traditional ripening cycle, in different locations. A significant influence of environmental conditions was observed, especially air velocity and humidity, affecting physical-chemical, microbiological and sensory characteristics. Locations with higher air velocity, presented cheeses with lower moisture content, higher mesophilic bacteria count, darker appearance and higher number of holes. Locations with higher humidity presented cheeses with lower scores on some sensorial parameters like appearance, firmness and intensity of odor. The results of computational fluid dynamics made possible the identification of areas in and around the cheese stacks were the air distribution is less than adequate or uneven, which may influence the evolution of cheese during ripening.

Applying Computational Fluid Dynamics in the Development of Smart Ripening Rooms for Traditional Cheeses.

Traditional ewe's cheese producers face certain challenges caused by fluctuating environmental parameters inside the ripening room, which lead to lack of homogeneity in the final product. The present research discusses the application of computer fluid dynamics for simulating the distribution of environmental parameters, predicting the airflow pattern, and identifying critical areas where such parameters could cause reduced cheese quality. A new monitoring system was developed including presence sensors, temperature and humidity dataloggers, pneumatic actuators, microcontrollers, and microcomputers connected remotely for control, data visualization, and processing. The validation of the computer simulation and monitoring system was made with a batch of 40 ewe's cheeses distributed in three different zones inside a prototype ripening room and ripened for 35 days. At 35 days, a physical, chemical, and microbiological characterization of cheeses was made for evaluation of the influence of environmental conditions on cheese quality. The comparison between simulated and local measurements showed close agreement, especially concerning air velocity inside the stacks of cheese. The results of Pearson's correlation analysis and PCA concluded that temperature affected the appearance of the rind, hardness, number and area occupied by holes. Humidity affected aw and mFeret. Air velocity affected pH and the circularity of gas holes.