Functional Properties of Camelina Protein Concentrate Extracted by Hot Oil-Pressing and Salt Precipitation and the Effect of Hydrolysis on Protein Functionality

Abstract

There is a continued demand for high protein foods, and plant proteins in particular are trending. Camelina is a sustainable oil seed that is emerging as a new potential protein source, although there is currently not much information available on camelina for food use. The objectives of this study were to characterize select functional properties of camelina seed after hot oil-pressing and extraction by salt precipitation. A portion of the resulting camelina protein concentrate was enzymatically hydrolyzed in attempt to improve solubility and functional properties. Whey protein isolate and soy protein isolate were also tested for comparison. SDS-PAGE was performed to characterize subunits within each protein. Solubility was measured at pH 3.4 and 7.0 under heated and non-heated conditions. The emulsification capacity, emulsion stability, gel strength, and water holding capacity were assessed. The solubility of camelina protein was slightly greater than SPI at pH 3.4 but inferior to WPI. At pH 7.0, the solubility of camelina protein was inferior to both WPI and SPI, which also led to inferior functionality as tests were conducted at pH 7.0. One notable exception was that the water holding capacity of camelina was equivalent to that of SPI with nearly 100% water retention. Hydrolysis at DH 8.6% was found to have a neutral or negative impact on all functional properties of camelina protein. Further research on camelina protein should be performed, particularly at an acidic pH to determine if its functional properties could be superior to SPI under acidic conditions.