Characterization of rice starch and protein obtained by a fast alkaline extraction method
Daiana de Souza1, Arthur Francisco Sbardelotto2, Denize Righetto Ziegler2
1Chemical Engineering Department, Federal University of Rio Grande do Sul (UFRGS), Rua Engenheiro Luiz Englert s/n, Porto Alegre/RS 90040-040, Brazil; Institute of Technology in Food for Health (itt Nutrifor), University of Vale do Rio dos Sinos (UNISINOS), Avenida Unisinos, 950, São Leopoldo/RS 93022-000, Brazil.
Abstract:
This study evaluated the characteristics of rice starch and protein obtained by a fast alkaline extraction method on rice flour (RF) derived from broken rice. The extraction was conducted using 0.18% NaOH at 30°C for 30min followed by centrifugation to separate the starch rich and the protein rich fractions. This fast extraction method allowed to obtain an isoelectric precipitation protein concentrate (IPPC) with 79% protein and a starchy product with low protein content. The amino acid content of IPPC was practically unchanged compared to the protein in RF. The proteins of the IPPC underwent denaturation during extraction and some of the starch suffered the cold gelatinization phenomenon, due to the alkaline treatment. With some modifications, the fast method can be interesting in a technological point of view as it enables process cost reduction and useful ingredients obtention to the food and chemical industries.
