Proteins Features of the Far Eastern Region Bivalve Mollusk Mactra Сhinensis

Abstract

Bivalve mollusk are protein raw materials, their soft tissues are characterized by a hard-rubbery consistency due to its proteins characteristics and should be considered when processing into food. The proteins fractional composition study of different groups (water-soluble, myofibrillar, and stroma) is an urgent task, since it is possible to justify the processing technology based on the obtained data. The article presents the fractional composition study results of the water-soluble proteins and peptides, the molecular mass distribution of the separate components of myofibrillary proteins and muscle tissue stroma proteins of the Mactra Chinensis mollusk motor muscle. The researchers noted that the total amount of the high-molecular fraction (molecular weight above 10 kDa) is 62.16 %, and the total peptide fraction amount (molecular weight below 10 kDa) is 37.84 %. There are four main components in myofibrillar proteins – myosin, actin, troponin complex components, and collagen. The content of the main myofibrillar protein that is myosin of various polymerization degrees of is 69.3 %; heavy myosin chains – 30.5 % of the total myofibrillar proteins content and 44.0 % of the relative content of the total myosin content; light myosin chains – 38.8 % of the total myofibrillar proteins content and 56.0 % of the relative content of the total myosin content. The authors determined that actin (molecular weight 43 kDa) and troponin complex components (molecular weight from 15 to 30 kDa) are approximately equal in content. The collagen content (molecular weight more than 300 kDa) in the myofibrillar fraction is only 8.2 %. Stroma proteins are represented by two main fractions with molecular weights of more than 250 and 500 kDa. Collagen is the predominant stroma protein, its content account for 62.6 %. There is a high connectin content in stroma proteins.