TÉCNICAS EXPEDITAS NA CARACTERIZAÇÃO FÍSICA DA CORTIÇA DESTINADA À PRODUÇÃO DE ROLHA

The present work aims to contribute for a better knowledge about the importance of image analysis and twisting test in the characterization of cork to stopper production. The samples were prepared for obtaining quantitative data on the calibre, apparent density, humidity, porosity, rupture strength and its angle. The classification resulting from this data was compared with the classification according the visual evaluating. The results of this study allow emphasizing that: The corks used for stoppers classified as very good, have low porosity with a high rupture strength and angle; The corks not used for stoppers with lower quality, have high values of image analysis, not allowing the manufacture of stoppers; Some samples don’t have visual characteristics suitable for the production of stoppers, however they were used to its production, according to the objective criterion; The planks that allow the stopper production, exhibit a relationship between the angle, the minimum size of pores and strain with the number of pores, the maximum area of pores and porosity, they act in inverse way; Comparing the results with those obtained by Pestana da Silva (2003), it was observed that these parameters allow an effective screening of cork qualification.