Characterization and Evaluation of Filmogenic, Polymeric, and Biofilm Suspension Properties of Cassava Starch Base (Manihot esculenta Crantz) Plasticized with Polyols / Caracterização e Avaliação das Propriedades Filmogénicas, Poliméricas e de Suspensão de Biofilme da Base de Amido de Mandioca (Manihot esculenta Crantz) Plastificado com Polióis

Abstract

This study investigated the gelatinization process of polymeric suspensions of cassava starch (Manihot esculenta Crantz) plasticized with glycerol or ethylene glycol and used for biofilm production. Scanning electron microscopy confirmed that the starch, used as raw material for suspensions, consists of granule-forming clods and granular aggregates. Physical parameters such as viscosity, density, and temperature can be evaluated and used to accurately characterize and identify the gelatinization point of the polyol-plasticized starch. Upon reaching the gelatinization point, the suspensions went underwent retrogradation and had a kinetic viscosity of 19 to 23.508 mPa·s for the starch–glycerol suspension and 13.56 to 16.12 mPa·s for the starch–ethylene glycol suspension. However, the density of the suspensions slightly decreased during this process, ranging from 1.01 to 0.98 g/cm3. The starch–glycerol biofilm was more malleable and resistant, while the starch–ethylene glycol biofilm was inflexible and brittle. The use of different polyols facilitated the modification of the solubilization capacity of the biofilms. The starch–glycerol biofilm had a solubility value three times higher than that of the starch–ethylene glycol biofilm. Keywords: Biofilms, starch, polyols, gelatinization, crystallinity. RESUMOEste estudo investigou o processo de gelatinização de suspensões poliméricas de amido de mandioca (Manihot esculenta Crantz) plastificado com glicerol ou etileno glicol e utilizado na produção de biofilme. A microscopia eletrônica de varredura confirmou que o amido, usado como matéria-prima para suspensões, consiste em torrões formadores de grânulos e agregados granulares. Parâmetros físicos como viscosidade, densidade e temperatura podem ser avaliados e utilizados para caracterizar e identificar com precisão o ponto de gelatinização do amido poliol plastificado. Ao atingir o ponto de gelatinização, as suspensões foram submetidas a retrogradação e tiveram uma viscosidade cinética de 19 a 23,508 mPa · s para a suspensão de amido-glicerol e 13,56 a 16,12 mPa · s para a suspensão de amido-etileno-glicol. No entanto, a densidade das suspensões diminuiu ligeiramente durante esse processo, variando de 1,01 a 0,98 g / cm3. O biofilme de amido-glicerol era mais maleável e resistente, enquanto o biofilme de amido-etileno-glicol era inflexível e quebradiço. O uso de diferentes polióis facilitou a modificação da capacidade de solubilização dos biofilmes. O biofilme de amido-glicerol apresentou um valor de solubilidade três vezes maior que o do biofilme de amido-etileno-glicol. This study investigated the gelatinization process of polymeric suspensions of cassava starch (Manihot esculenta Crantz) plasticized with glycerol or ethylene glycol and used for biofilm production. Scanning electron microscopy confirmed that the starch, used as raw material for suspensions, consists of granule-forming clods and granular aggregates. Physical parameters such as viscosity, density, and temperature can be evaluated and used to accurately characterize and identify the gelatinization point of the polyol-plasticized starch. Upon reaching the gelatinization point, the suspensions went underwent retrogradation and had a kinetic viscosity of 19 to 23.508 mPa·s for the starch–glycerol suspension and 13.56 to 16.12 mPa·s for the starch–ethylene glycol suspension. However, the density of the suspensions slightly decreased during this process, ranging from 1.01 to 0.98 g/cm3. The starch–glycerol biofilm was more malleable and resistant, while the starch–ethylene glycol biofilm was inflexible and brittle. The use of different polyols facilitated the modification of the solubilization capacity of the biofilms. The starch–glycerol biofilm had a solubility value three times higher than that of the starch–ethylene glycol biofilm.