Banca de QUALIFICAÇÃO: LAURA GABRIELA GURGEL DE CARVALHO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : LAURA GABRIELA GURGEL DE CARVALHO
DATA : 31/07/2019
HORA: 14:00
LOCAL: Sala de aula do LAPET
TÍTULO:

HYDROPHOBIZATION OF STARCH EXTRACTED FROM MANGO KERNEL AND ITS APPLICATION IN STARCH FILMS FOR FOOD PACKAGING

PALAVRAS-CHAVES:

Starch, laurate starch, biodegradable films

PÁGINAS: 70
GRANDE ÁREA: Ciências Exatas e da Terra
ÁREA: Química
SUBÁREA: Química Orgânica
ESPECIALIDADE: Polímeros e Colóides
RESUMO:

After the industrial processing of the mango, portions of the fruit, such as peel and seed, are discarded without proper use. About 15% of the weight of the mango is due to the seed, from which it is possible to obtain the starch. Thus, the use of mango starch to obtain biodegradable films that add value to industrial waste is very promising. However, although starch films have advantages related to renovation and biodegradation, they have limitations on their mechanical and barrier properties. Therefore, in this work, the chemical modification of the starch from mango kernel with vinyl laurate was performed and the incorporation of this product, as a structuring agent, to the starch films of the unmodified mango, was carried out. Thus, this study evaluated the influence of the incorporation of different concentrations of starch laurate (SL) on starch film on its mechanical and physical properties. The polymers were characterized by neutralization volumetry, NMR, IR, TG and XRD. The chemical modification of the starch was confirmed by Fourier Transform Spectroscopy (FTIR), through the appearance of C=O band of saturated ester at 1743 cm^-1, of lower frequency than the C=O band from the vinyl ester, at 1758 cm^-1. The degree of chemical modification of the starch by laurate group determined by volumetry was 0.28. The starch from mango kernel presented type A crystallinity, whereas the SL presented only two broad and dispersive peaks, corresponding to an amorphous material. The films prepared with different concentrations of LA (0-15% weight/weight, based on the starch concentration) by microfluidization, were submitted to tensile, opacity, water vapor permeability (WVP) and X-ray diffraction analyses. The addition of SL resulted on an improved elongation at break, higher opacity, and lower tensile strength and Young's modulus. The microfluidification step was determinant to obtain lower values of WVP. The X-ray diffraction (XRD) results for the films corroborated the mechanical properties, showing that LA incorporation reduces the crystallinity of the starch films.

MEMBROS DA BANCA:
Interno - 1198847 - JOSE LUIS CARDOZO FONSECA
Interna - 1569526 - RENATA MENDONÇA ARAUJO
Presidente - 1149440 - ROSANGELA DE CARVALHO BALABAN