Full text
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| Author(s): |
Nirse Ruscheinsky
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia Química |
| Defense date: | 2005-02-28 |
| Examining board members: |
Theo Guenter Kieckbusch;
Denise Calil Pereira Jardim;
Renato Grimaldi
|
| Advisor: | Valdecir Luccas; Theo Guenter Kieckbusch |
| Abstract | |
Natural cupuasu (Theobroma grandiflorum Shumann) fat was neutralized and its composition and physical/chemical properties were evaluated. The polimorphic crystallization behavior of the neutralized fat was investigated using Polarized Light Microscopy (PLM), Differential Thermal Analysis (DSC) and X-ray Diffraction using Synchrotron Radiation (SR-XRD). The PLM technique indicates a tendency of the cupuasu fat to crystallize in the 'beta¿-form. The study with the C and SRXRD confirmed the existence of three crystalline forms. The neutralized cupuasu fat was submitted to dry thermal fractionation procedures, following a '2 POT 2¿ complete factorial design' with three central points and crystallization temperature and rotational velocity to be the independent variables, in order to obtain stearin and olein fractions. The response factors were the yield in stearin (%est), the fractionation time (tf), the difference between the lodine Index of the stearin fraction and the olein fraction ('delta¿Ii), the difference in melting point of the stearin and the olein fractions ('dleta¿Pf), the solid content of the stearin at '25GRAUSC¿ (Se¿25GRAUS¿C) and the difference between the stearin solid content at '25GRAUS¿¿ and '35GRAUS¿C (Se¿25GRAUS¿C '35GRAUS¿C). The recommended optimal conditions from the operational cost point of view is a crystallization temperature range from '29,2GRAUS¿ to '29,5GRAUS¿C and a stirrer rotation speed between 25 and 30rpm. In terms of stearin quality, represented by the capacity of separation ('delta¿Ii and 'delta¿Pf) the best conditions are situated at a temperature range of 28 to '28,4GRAUS¿C and a rotation speed between 20 and 21,2rpm (AU) | |