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| Author(s): |
Juliana Martin do Prado
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos |
| Defense date: | 2010-08-16 |
| Examining board members: |
Maria Angela de Almeida Meireles Petenate;
Miriam Dupas Hubinger;
Patricia Franco Leal;
Marcio Antonio Mazutti;
Sandra Regina Salvador
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| Advisor: | Maria Angela de Almeida Meireles Petenate |
| Abstract | |
The objective of the present work was to evaluate the technical and economical viability of installing an industrial scale supercritical fluid extraction (SFE) plant in Brazil. In this work, clove (Eugenia caryophyllus) was selected as model raw material. The validation of the methodology proposed was done using raw materials of different agronomic profiles and extract types: ginger (Zingiber officinale), sugarcane (Saccharum spp) residue, lemon verbena (Aloysia triphylla) and grape (Vitis vinifera) seed. For lab scale experiments, two SFE units with extraction vessels of different volumes were used, of 4.6 to 290 mL, to obtain global yield and extraction kinetics data. The process parameters established by fitting the extraction curves were used to adapt the process from lab scale to a pilot plant equipped with a 5 L extractor. The chemical analyses of the extracts were done by gas chromatography, thin layer chromatography and other techniques, to determine the phytochemical profile of the products obtained. Global yield and chemical composition data were evaluated to determine optimum extraction temperature and pressure for two raw materials: clove (313 K/15 MPa) and ginger (313 K/30 MPa). After determining the overall extraction curves at lab scale for the five raw materials, the scale-up criterium adopted was maintaining solvent to feed ratio (S/F) constant. The curves previously determined at lab scale were successfully reproduced for 14-17 fold scale-up to pilot scale for all raw materials. The separation step of SFE process was studied at pilot scale, using three separators displayed in series, operating under different temperature and pressure conditions. Extracts of different physical aspects and chemical compositions were obtained by manipulating the separators operation conditions, characterizing different products. The stability of ginger extract stored at 255 K was evaluated; during the first 4 months of storage there was significant alteration of the extract¿s chemical composition, and during the next 18 monts it was stable. From manufacturing cost calculated for the extracts, it was demonstrated that the SFE process is economically viable in Brazil for industrial scale extractors of 50 to 500 L, depending on the raw material processed. Gathering technical and economical data, for clove, SFE at 313 K/15 MPa, 52 min and S/F of 3.6 presents the best relation between cost, yield and product quality. For sugarcane residue, the optimized parameters were 60 min and S/F of 4.8 at 333 K/35 MPa. As for grape seed, SFE at 313 K/35 MPa, 240 min and S/F of 6.6 were the selected parameters (AU) | |