Protein concentrates from defatted rice bran: preparation and characterization

Abstract The goal of this work is to determine the optimal conditions for the obtaining of protein concentrates from rice bran. The effects of defatting processes applied to this product in laboratory and in industrial scales were investigated. Through two experimental designs were performed, and production conditions to obtain the protein concentrates were chosen with values of protein contents average 59.9% and 57.1%, with protein yields of 61.6% and 30.7%. The concentrates produced with industrially defatted rice bran showed higher digestibility and increased thermal stability compared with the product obtained with laboratory defatted rice bran. Both concentrates show molecular weight proteins below 50 kDa. The morphology of the precipitated proteins, analyzed by scanning electron microscopy, there was a great difference in the size of particles, which form the wet precipitates. The differences presented by the concentrates can be due to defatting processes which raw materials were submitted. Thus, studying the protein extraction conditions and knowing its characteristics is very important for the industry, because food processing requires knowing the behavior of each compound during and after processes they will be submitted.