Extraction of Citrus maxima: design of experiments by Taguchi method

This master thesis contains experimental research about relative impact of significant process parameters that influence the pomelo´s (Citrus maxima) extraction using Taguchi design methodology. Orthogonal array L18 was selected for the proposed design and ANOVA method was used for recognizing the relative influence of the process parameters. Six different studies have been carried out: To obtain a high yield of the pomelo extraction the most important parameters were: Pomelo´s material, ratio between mass of material and volume of solvent and type of extraction. The content of total extracted phenols (according to the Folin-Ciocalteu procedure) was analyzed by UV spectrophotometry. The most influential parameters were Pomelo´s material and ratio between mass of material and volume of solvent. Extracts were analyzed for the contents of naringin by high performance liquid chromatography (HPLC). The analysis was performed by solubiliring the extracts in methanol. The most important parameters for extraction of naringin were: Pomelo´s material, ratio between mass of material and volume of solvent, time, type of extraction and temperature. For determination of antioxidant properties of extracts three different methods were used. The radical-scavenging activities of pomelo extract were evaluated using the stable free radical 2,2-diphenyl-1-picrylhidrazyl (DPPH·). The most influential parameters were: temperature, pomelo’s material and kind of solvent. The most influential parameters for antioxidant properties of extracts determined by ACW method (water soluble antioxidant capacity) were: Pomelo´s material and ratio between mass of material and volume of solvent, while for lipid soluble antioxidant capacity (ACL) the most influential parameters were: time, solvent percentage, pomelo´s material, type of extraction and kind of solvent.Outgoin