RESUMEN
European ash (Fraxinus excelsior L.) is one of the species commonly used for wood thermal modification that improves its performance. The presented research aimed to investigate a moisture-dependent strength anisotropy of thermally-modified European ash in compression. Wood samples were modified at 180 °C and 200 °C. Their mechanical parameters were determined in the principal anatomical directions under dry (moisture content of 3%) and wet (moisture content above fibre saturation point) conditions. Effect of heat treatment temperature and moisture content on the ash wood mechanical parameters concerning each anatomical direction were determined. The results show that thermal treatment kept the intrinsic anisotropy of wood mechanical properties. It decreased wood hygroscopicity, which resulted in improved strength and elasticity measured for wet wood when compared to untreated and treated samples. Higher treatment temperature (200 °C) increased wood elasticity in compression in all the anatomical directions despite wood moisture content during the measurements. Multivariate analysis revealed that the modification temperature significantly affected the modulus of elasticity perpendicular to the grain, while in the case of compression strength, the statistically significant effect was observed only parallel to the grain. The results obtained can be useful from an industrial perspective and can serve as part of a database for further modelling purposes.
RESUMEN
Guidelines for estimation of food additives intake were prepared by Codex Committee on Food Additives and Contaminants (CCFAC) in 1989. During the period 1994, 1995 three specific directives have been adopted, each of them including an obligation for Member States to introduce systems to monitor the usage and consumption of food additives and to report their findings to the Commission. Recommendations of Commission's experts which should be taken into account for preparing the monitoring system by Member States are based on decision tree, which systematizes proceeding procedures. Above mentioned decision tree might be a tool for elimination of the food additive which intake does not pose a health hazard. ADI (Acceptable Daily Intake) plays the essential role in the risk assessment of food additives intake. The food additives, which were not eliminated during the decision tree considerations require detailed revision of the conditions of their use. Poland, as a Candidate Country for EU, after the accession will also be obligated to introduce the system to monitor the usage and consumption of food additives and to report relevant report to the Commission.