Banca de DEFESA: LAURA GABRIELA GURGEL DE CARVALHO

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : LAURA GABRIELA GURGEL DE CARVALHO
DATE: 21/07/2020
TIME: 14:00
LOCAL: Remotamente por aplicativo
TITLE:

Mango almond starch esters: synthesis, characterization and applicability study in films for food packaging and reverse emulsion systems

KEY WORDS:

Mango kernel starch esters: synthesis, characterization and study of application in films for food packaging and reverse emulsion systems

PAGES: 70
BIG AREA: Ciências Exatas e da Terra
AREA: Química
SUBÁREA: Química Orgânica
SPECIALTY: Polímeros e Colóides
SUMMARY:

After the industrial mango processing, portions of the fruit, such as peel and seed, are discarded without proper use. About 15% of the weight of mango is due to the seed, from which it is possible to obtain starch. Thus, the use of mango starch to obtain inputs that add value to industrial waste is quite promising. However, although starch is an advantageous polymer because it is biodegradable and obtained from a renewable source, it has limitations for certain industrial applications. In this context, chemical modification of the mango almond starch with vinyl laurate was carried out, with the aim of overcoming these limitations. The production of the starch ester was confirmed by infrared (IV) and nuclear magnetic resonance (NMR). The applied synthesis conditions led to the production of starch laurate with degrees of substitution 2.4 (SL1) and 0.28 (SL2). Mango almond starch showed type A crystallinity. On the other hand, its esters lost the crystallinity pattern corresponding to the granule, presenting wide and dispersive peaks, corresponding to an amorphous material. Several mixtures of starch and starch laurate were used in the preparation of polymeric films, and their mechanical and physical properties were evaluated. Starch laurate with a high degree of substitution (SL1) did not show good results in any of the methods used in the preparation of films. In turn, starch laurate with a low degree of substitution (SL2) showed promising results. The films of starch and starch laurate mixtures, with a maximum concentration of 15% for SL2 (in relation to starch), prepared by microfluidization, showed greater elongation at break, greater opacity, lower stress at break and lower Young modulus than the pure starch films. The microfluidization step was decisive for obtaining films with low water vapor permeability values. In a second aspect of applicability, SL1 (starch laurate with degree of substitution 2.4), which did not present good properties in films for food packaging, had its performance evaluated as a rheological modifier in an emulsion of brine in olefin, aiming application in drilling fluids. Unlike starch and SL2, SL1 showed good solubility in olefin and provided a significant increase in viscosity in the reverse emulsion used as a model.

BANKING MEMBERS:
Presidente - 1149440 - ROSANGELA DE CARVALHO BALABAN
Externo à Instituição - ADRIANO LINCOLN ALBUQUERQUE MATTOS - EMBRAPA
Externo à Instituição - MARCUS VINICIUS GOMES PAIXÃO
Externa à Instituição - Nívia do Nascimento Marquês
Externo à Instituição - ROSSANA MARA DA SILVA MOREIRA THIRÉ - UFRJ