Full text
| |
| Author(s): |
Sungil Ferreira
Total Authors: 1
|
| Document type: | Doctoral Thesis |
| Press: | São José do Rio Preto. 2021-01-06. |
| Institution: | Universidade Estadual Paulista (Unesp). Instituto de Biociências Letras e Ciências Exatas. São José do Rio Preto |
| Defense date: | 2020-12-04 |
| Advisor: | Vânia Regina Nicoletti |
| Abstract | |
Complex coacervation is a versatile microencapsulation technique capable of encapsulating and protecting hydrophobic and hydrophilic compounds. In addition, it is able to protect encapsulated core materials from different adverse conditions such as light, oxygen and low pH during digestion. However, due to its very nature, the technique has some limitations that prevent it from being applied on a large scale or in non-batch processes. This work proposes a few alternatives in order to facilitate the application of the complex coacervation technique on a larger scale. In the traditional complex coacervation process, polymeric solutions are mixed and then the pH is adjusted to promote interaction and subsequent coacervation. A new configuration has been developed in which complex coacervation is induced by the atomization of the emulsified core material in a protein solution over the polysaccharide solution; in this particular case, ginger oil emulsion in gelatin over aqueous solution of gum Arabic. Complex coacervation by atomization, in addition to being a promising method for producing capsules, opens up the possibility of predicting their final size depending on atomization conditions or representative dimensionless numbers. An important bottleneck in the complex coacervation process to be considered is the cure of the capsules. Traditionally, curing is carried out in batches in a slow cooling process. In this work it is proposed to use a tubular heat exchanger with controlled pumping and temperature to cure the capsules in a continuous process. Thus, the time required in the curing stage has decreased considerably, opening up new opportunities to increase the scale and carry out the coacervation process as a whole in a semi-continuous manner. The use of metallic membranes for the formation of emulsions to be used during the complex coacervation process was also evaluated, in addition to the use of this same configuration of membranes to induce complex coacervation, as a new method. This is important because there are already systems for using membranes on an industrial scale and in a continuous process, which can eventually be adapted to carry out the complex coacervation process in a continuous mode. The capsules formed by atomization were equal to or better than the capsules produced by the traditional method, considering size, morphology and encapsulation properties. The cure of the capsules in the heat exchanger proved feasible, with promising results, and thus the complex coacervation in a semi-continuous process was made possible. (AU) | |
| FAPESP's process: | 15/23290-0 - Development of semi-continuous processes for production of ginger oil (Zingiber officinale Roscoe) microcapsules by complex coacervation: atomization and membrane emulsification |
| Grantee: | Sungil Ferreira |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |