Properties of Protein Isolates from Marine Hydrobionts Obtained by Isoelectric Solubilisation/Precipitation: Influence of Temperature and Processing Time
Svetlana R. Derkach, Yuliya A. Kuchina, Daria S. Kolotova, Ludmila A. Petrova, В. И. Волченко, Andrei Yu. Glukharev, Vladimir A. Grokhovsky
Abstract
Protein isolates were obtained from marine hydrobionts by the method of isoelectric precipitation with a preliminary stage of protein alkaline solubilisation. Northern blue whiting was chosen as the raw material. Various technological modes of the solubilisation stage were used: the temperature of the reaction mixture was 4 or 20 °C, and the duration was 4 or 16 h. The yield of the product was 44-45% with a high content of the main component (protein) equal to about 95%. It has been shown that a decrease in the temperature and duration of the alkaline solubilisation stage provides the production of protein isolates with good technological properties, a low solubility, high swelling and high emulsifying ability, necessary for its use in the production of functional food products, including therapeutic and prophylactic effects. These technological properties are explained by a change in the composition and structure of the protein, the change being an increase in the content of essential amino acids and the proportion of α-helices in the polypeptide chain. The main patterns obtained will be used to obtain protein isolates from marine molluscs.