Search

Thermal and rheological properties of methylcellulose (MC) and hydroxypropyl methylcellulose (HPMC) hydrogels with chitosan (CHI) were investigated to verify the potential application of these blends as structured systems for oil transport (emulgel, oleogels, and bigels). FTIR confirmed hydrophobic interactions of cellulosic polymers with chitosan. In the temperature sweep, the thermosensitive hydrogels showed their reduced gel point compared to the original polymers. The gelation temperature was reduced from 66.9 °C for pure HPMC to 43.6 °C and 43.6 °C (MC pure polymer) to 39.3 °C when 30% CHI was added for both cases. The addition of 20 and 30% chitosan is enough to modify the extension of the gelation temperature of these polymers. These results indicate that the addition of chitosan enables MC and HPMC to form gels at lower temperatures, which could allow milder thermal conditions to be applied in processing oil carrier systems.

The aim of this work was produce and characterize solid lipid microparticles (SLMs) with different proportions of fully hydrogenated palm oil (FHPO) and palm oil (PO) as wall material (WM) to encapsulate ascorbic acid (AA), using the spray chilling technique. The microparticles were evaluated for surface morphology (SEM), size distribution and mean diameter, polymorphism, encapsulation efficiency, thermal behavior, DSC, and for release profile. The mean particle diameter ranged from 97.80 to 181.29 μm and the micrographs revealed spherical particles and rough surfaces. The encapsulation efficiency ranged from 80.22 to 93.51% and it was influenced by increases in the concentration of PO in each formulation and by the particle size. All the lipid microparticles presented high thermal resistance and had crystalline behavior β′, proving that after atomization the particles preserved the original polymorphic forms of their constituent materials. Moreover, SLMs gradually released ascorbic acid in aqueous medium, following Higuchi kinetic.

O presente trabalho teve como objetivo desenvolver uma formulação de pão francês com 50% de redução no teor de sódio (Na+), avalição sensorial do produto sem veículo e com veículo (margarina) e a avaliação estatística dos resultados. As análises físico-químicas seguiram a metodologia estabelecida pelo Instituto Adolfo Lutz (2008). Já para a análise sensorial foi utilizado um método afetivo, utilizando 79 provadores para a primeira avaliação e para a segunda 95 provadores, tendo como referência mínima de aceitação o índice de 70%. Para os resultados de composição centesimal o produto atende a especificação legal. Na avaliação dos parâmetros sensoriais percebe-se que os índices de aceitação dos produtos sofrem interferência quando são oferecidos com veículo (margarina). Assim com base nos resultados obtidos neste projeto mostram que é possível desenvolver um produto com 50% de redução de sódio, dentro do padrão legal estabelecido.