Banca de DEFESA: ALINE CORTINES DE ALMEIDA GUENA
Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.DISCENTE : ALINE CORTINES DE ALMEIDA GUENA
DATA : 08/08/2019
HORA: 09:00
LOCAL: Seropédica
TÍTULO:
ENCAPSULATION OF VITAMIN C BY COMPLEX COACERVATION USING XANTAN GUM AND PROTEIN AS WALL MATERIALPALAVRAS-CHAVES:
Ascorbic acid, Anionic polysaccharide, Lactoferrin, Pig gelatin, Complex coacervates.
PÁGINAS: 93
GRANDE ÁREA: Ciências Agrárias
ÁREA: Ciência e Tecnologia de Alimentos
SUBÁREA: Ciência de Alimentos
ESPECIALIDADE: Química, Física, Fisico-Química e Bioquímica dos Alim. e das Mat-Primas Alimentares
RESUMO:
Microencapsulation is used in the food technology to protect bioactive compounds susceptible to degradation during processing, such as ascorbic acid, which is a vitamin with antioxidant properties but highly unstable. Biopolymers have been used as wall materials because of their influence on the formation and stabilization of microcapsules through the complex coacervation technique. The microencapsulation of ascorbic acid protects it, enables its application in new foods and prevents undesirable sensorial changes. The aim of this work was the production of ascorbic acid microcapsules formed by double emulsification followed by complex coacervation of xanthan gum with two different proteins: lactoferrin or gelatine type A. The coacervate complexes had their formation evaluated in relation to the pH and the ratio of the biopolymers by zeta potential and turbidimetry. The coacervates formed between the protein and polysaccharide in a ratio of 6:1 at pH 5.0 for the lactoferrin-containing system and at a ratio of 2: 1 at pH 4.0 for the gelatin system were the ones with the best yields, therefore applied for microencapsulation, using different ratios of core and wall material. The microcapsules with best efficiencies, E4 for lactoferrin-containing system and E5 for the gelatin system, yielding 83.19 ± 0.37% and 73.60 ± 0.71%, respectively, had their morphology and stability evaluated as well as their thermal behavior, assessed by TGA and DSC. Although higher encapsulation efficiency was obtained by the lactoferrin-containing system, the best overall performance of the study was achieved by microcapsules containing gelatin, which showed better stability and thermal properties, providing better protection of ascorbic acid for at least 30 days at 25 ° ± 1.3 ° C. In both microcapsule systems studied, there was an increase in thermal stability, compared to free ascorbic acid, provided by the complex coacervation between biopolymers, which would allow the application of these capsules in food baked or fryied products, such as breads, cookies or hamburgers.
MEMBROS DA BANCA:
Presidente - 014.548.996-54 - EDWIN ELARD GARCIA ROJAS - UFF
Interno - 2311373 - MARIANA TEIXEIRA DA COSTA MACHADO
Externo à Instituição - ELIANA DA SILVA GULÃO - UFRJ