Biochemical and Functional Properties of Myofibrils from Preand Post‐Spawned Hake (Merluccius hubbsi Marini) Stored on Ice

Abstract

Enzymatic activities assayed at beginning of storage in myofibrils from post-spawned hake were 3 X those in myofibrils from pre-spawned hake. Ca2+ sensitivity of myofibrils from pre-spawned hake was 40% less than that of myofibrils from post-spawned hake. The profiles of SDS-PAGE gels of pre-spawned myofibrils at beginning of storage showed a partially denatured myosin heavy chain, and polypeptide bands under myosin heavy chain. They probably represent proteolytic fragments produced by degradation of MHC in vivo. No proteolysis was detected in myofibrils during storage. These results help predict functional properties of fish proteins and changes during storage.

Physicochemical and enzymatic changes of cod muscle proteins subjected to different freeze-thaw cycles

“…The Ca 2 sensitivity of myo®brillar proteins is attributed to the activity of native tropomyosin 29 and was reported as a good indicator for Ca 2 regulation of myo®brillar proteins. 26 The loss of Ca 2 sensitivity was presumed to be caused by proteolysis.…”

Functional properties of Rohu (Labeo rohita) proteins during iced storage

“…Changes in the quality of fish during storage in ice have been extensively studied (Benjakul, Visessanguan, & Tueksuban, 2003;Grigorakis, Taylor, & Alexis, 2003;Ozogul et al, 2005;Reddy & Sirkar, 1991;Roura & Crupkin, 1995;Ruiz-Capillas & Moral, 2001;Wang, Liceaga-gesualdo, & Li-Chan, 2005). K-value, the ratio derived from the degradation of nucleotides, is a commonly used biochemical index to monitor freshness of fish during storage (Bremner, Olley, Statham, & Vail, 1988;Lakshmanan & Gopakumar, 1996;Ryder, 1985;Yongsawtdigul & Park, 2002).…”

“…Other functional properties like emulsion, foaming, etc., find application in the development of comminuted fish products like sausages and battered products. Only limited literature is available on change in functional properties in fish proteins during ice storage (Parthiban, Sankar, & Anandan, 2005;Reddy & Sirkar, 1991;Roura & Crupkin, 1995;Wang et al, 2005) and frozen storage (Careche & Tejada, 1990;Huidobro & Tejada, 1992). This study aims to investigate the functional properties of rohu (Labeo rohita) proteins in relation to conformational changes during storage in ice.…”

Physicochemical changes of myosin and gelling properties of washed tilapia mince as influenced by oxidative stress and microbial transglutaminase

“…As a consequence, those radicals could induce the oxidation of protein, leading to the loss of ATPase activity found at the head of myosin heavy chain. Ca 2+ -ATPase activity is considered to be a good indicator of integrity of myosin molecule (Roura and Crupkin 1995).…”