Orientadores: Antonio Jose de Almeida Meirelles, Roberta Ceriani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenahria de Alimentos / Made available in DSpace on 2018-08-12T23:20:41Z (GMT). No. of bitstreams: 1 Taham_Thiago_M.pdf: 2455225 bytes, checksum: c1d9574336bac7f84b970238a9896a58 (MD5) Previous issue date: 2009 / Resumo: A etapa de desacidificação por via física deve ser delineada de forma a aproveitar a grande diferença na volatilidade dos compostos indesejáveis e do óleo neutro sob altas temperaturas e vácuo, sem causar danos importantes aos nutracêuticos, sem produção excessiva de ácidos graxos trans e sem perda elevada de óleo neutro. Aprimorar as condições operacionais desta importante etapa do refino de óleos vegetais é um assunto relevante atualmente. Neste sentido, o uso de ferramentas computacionais na análise dos efeitos das variáveis de processo e da variabilidade da matéria-prima na qualidade do produto final torna-se bastante interessante. No entanto, a modelagem matemática de sistemas químicos complexos, como os óleos vegetais, demanda o levantamento de uma grande variedade de propriedades físicas e métodos preditivos, cuja acurácia pode ser questionada. Dentro deste contexto, o presente trabalho investigou experimentalmente o processo de desacidificação por via física em batelada de sistemas-modelos graxos de composição conhecida (triacilgliceróis + ácidos graxos + tocoferol), seguindo planejamentos fatoriais, e validou os resultados finais das respostas de interesse, acidez final, concentração de nutracêuticos e perda de óleo neutro, gerados por simulação computacional nas mesmas condições de processo. Os desvios médios encontrados foram satisfatórios e comprovaram a capacidade da ferramenta de simulação de prever os valores finais próximos dos reais / Abstract: The steam deacidification step must be designed in order to take into account the high difference in the volatility of undesirable compounds and the neutral oil under high temperatures and vacuum, without causing damage to nutraceutical compounds, excessive production of trans fatty acids and neutral oil loss. To improve the process conditions of this important stage of vegetable oils refining is a relevant topic nowadays. Thus, using computacional simulation in the effect analysis of the process variables and the variability of raw material in the final product quality becomes relevant. However, the mathematical modeling of complex chemical systems, such as edible oils, requires knowledge of a wide variety of physical properties and predictive methods, whose accuracy can be questioned. This work studied experimentally the steam deacidification process of fatty model-systems with known composition (triacylglycerol + fatty acids + tocopherol), following experimental designs, and tried to validate the results responses of interest (final acidity, neutral oil loss and nutraceutical content), generated by computational simulation under the same process conditions. The mean deviation was satisfactory and showed the computational simulation ability to predict final results close to the real ones / Mestrado / Mestre em Engenharia de Alimentos

Στην παρούσα διατριβή, αναπτύχθηκαν και εφαρμόστηκαν πρωτοποριακές διεργασίες, με σκοπό την απολύμανση και την απόσμηση των φλοιών φελλού και των φυσικών φελλών. Στόχος της απολύμανσης του φελλού είναι η μείωση του μικροβιακού του φορτίου, τόσο σε βακτήρια όσο και σε ζύμες-μύκητες, ενώ με την απόσμησή του επιχειρείται η μείωση της άμεσα απελευθερούμενης 2,4,6-Τριχλωροανισόλης (2,4,6-TCA) που περιέχεται σε αυτόν. Η εφαρμογή της διεργασίας του απλού οζονισμού αποδείχθηκε ιδιαίτερα ικανοποιητική στην επεξεργασία των φλοιών φελλού, ενώ συγκρίσιμα αποτελέσματα λήφθηκαν και μέσω της απλής ή παλμικής έκθεσής τους στον ατμό. Στην περίπτωση των φυσικών φελλών, είτε πρόκειται για τεχνητά ή φυσικά μολυσμένους και με βάση τεχνοοικονομικά κριτήρια, επιλέχθηκε ως βέλτιστη διεργασία, η παλμική διεργασία με έκθεση στον ατμό (SPP). Για την πληρέστερη περιγραφή της απόσμησης των φελλών, υλοποιήθηκε κατάλληλο μαθηματικό μοντέλο, του οποίου οι κρίσιμες παράμετροι προσδιορίστηκαν μετά από προσομοίωση των αποκτηθέντων πειραματικών αποτελεσμάτων. Στο δεύτερο μέρος της παρούσας διατριβής, μελετήθηκε η απόσμηση των φυσικών φελλών με χρήση εμπορικών προσροφητικών μέσων, διαμέσου της υγρής και αέριας φάσης και ως καταλληλότερο επιλέχθηκε το πολυμερές Tygon. Τέλος, προκειμένου να λάβει χώρα η διαχείριση της 2,4,6-TCA που αποβάλλεται από τους φελλούς κατά την απόσμησή τους στην υγρή και αέρια φάση, δοκιμάστηκε η χρήση διάφορων οξειδωτικών μέσων. / Novel processes for sterilization and deodorization of cork stoppers and cork barks have been developed and evaluated. Cork sterilization targets to microbial load reduction, either for bacteria or yeasts-moulds, while the reduction of rapidly releasable 2,4,6-trichloroanisole (2,4,6-TCA) of cork is achieved via their deodorization. The application of the plain ozonation process proved to be particularly efficient in cork barks treatment, while similar results were achieved using their plain or pulsed steam exposure. In the case of naturally or artificially contaminated cork stoppers, the steam pulsed process (SPP) was chosen as the optimum, based on techno economical criteria. The detailed description of cork deodorization was based on an appropriate mathematical model and the determination of its critical parameters was carried out via the simulation of the obtained experimental results. In the second part, the cork deodorization using commercially available adsorption materials via gas or liquid phase was studied and the polymer Tygon was chosen as the optimum. Finally, the management of 2,4,6-TCA, as a waste from cork deodorization in liquid and gas phase was tested using various oxidizing agents.