Comparison of Drying Techniques for Extraction of Bioactive Compounds from Olive-Tree Materials

Olive tree vegetal materials are considered a powerful source for the isolation of bioactive compounds—mainly phenols and triterpenic acids. However, high humidity content them reduces their preservation extractability to liquid solvent. Accordingly, drying step is crucial homogenize material obtain an efficient extraction. We studied influence process on extraction efficiency compounds from olive material. For this purpose, we evaluated effects four processes solid–liquid two by-products, leaves pomace, fruits harvested cultivars, Alfafara Koroneiki. Infrared-assisted (IAD) was most suited approach extracts enriched in oleuropein (28.5 22.2% dry weight Koroneiki, respectively). In case lyophilization microwave-assisted led concentrated oleacein aglycone, whereas IAD oven-drying with enhanced contents hydroxytyrosol glucoside hydroxytyrosol, respectively. The considerably affected chemical composition obtained fruits. Changes were explained essentially by conditions using auxiliary energies, temperature, time, which promoted alterations increased compounds. Therefore, protocol should be selected depending phenolic initial raw