Relação entre tempo de exposição e concentração de ácido lático nas características de expansão do amido de mandioca modificado

• Main Author: Santos, Thaís Paes Rodrigues dos [UNESP]
• Publication Date: 2012
• Other Authors: Sartori, Maria Márcia Pereira [UNESP], Cabello, Cláudio [UNESP]
• Format: Article
• Language: por
• Source: Repositório Institucional da UNESP
• Download full: http://revistas.fca.unesp.br/index.php/rat/article/view/1067; http://hdl.handle.net/11449/141188
• topic: Specific volume; Carboxyl groups; Carbonyl groups; Volume específico; Grupos carboxil; Grupos carbonila

The cassava starch is a starch modified by a photochemical process of anaerobic fermentation and drying in the sun with no standardization of the production process, which is undesirable especially for applications in industry foods. Many studies have been conducted to investigate factors that determine the development of the property expansion of the cassava starch and showed that the lactic acid fermentation and sun exposure are most important. From this, the present study aimed to evaluate changes in the oxidation of cassava starch with different concentrations of lactic acid and drying at different times of UV exposure, seeking a process protocol to produce desirable characteristics of the food industries. The starches have been modified by wet oxidation with lactic acid solution to 1.0, 2.0 and 3.0% at room temperature for 10 minutes, with constant stirring. Then were recovered by filtration vacuum and exposed to UV radiation by 20, 40 and 60 minutes, with final drying in an oven air circulation. Were analyzes performed of specific volume, groups carbonyl and carboxyl and compared with native starch from cassava (AMN) and industrial modified cassava starch (AMMC). The results of three analysis performed did not differed statistically (p <0.05) between treatments, but differed in relation to the comparative samples. Compared with the native starch sample the results of the carboxyl groups analyses were lower and carbonyl groups and specific volume were higher. These results showed don't to have relation between the increase carboxyl groups with increase of the expansion. It was conclude that modification of native cassava starch with addition of lactic acid and exposure to UV radiation causes changes in the characteristics of the same, but there is no relationship between carboxyl groups with expansion.