Gelling Properties of Actomyosin from Pre‐ and Post‐Spawning Hake (Merluccius hubbsi)

Abstract

The biochemical properties and the characteristics of heat-induced gelation of natural actomyosin (NAM) from pre-and post-spawning hake were studied. 2+Mg ATPase activity, reduced viscosity and myosinl actin mole ratio of NAM from post-spawning fish were higher than those of pre-spawning ones. Gelation of both actomyosin at 10 mg mL-' of protein concentration was optimal at 60°C and pH 6.0. The highest rigidity was reached at 0.40M and 0.44M KC1 with NAM from pre-and post-spawning hake, respectively. Irrespective of heating temperature, ionic strength conditions and at pH range 5.5-7.5, rigidity of post-spawning hake NAM gels was higher than those of pre-spawning fish. Scanning electron micrographs of pre-and postspawning hake NAM showed "actin-type" and "myosin-type" ultrastructures, respectively.

Thermally Induced Gelation of Squid (Illex argentinus) Actomyosin. Influence of Sexual Maturation Stage

“…As a consequence of that, rigidity of squid actomyosin heat-induced gelation increases proportionally to the protein concentration, irrespective of the sexual maturation stage of the specimens. Similar results were reported for reconstituted red actomyosin and hake actomyosin Beas et al, 1988).…”

“…It has been reported that depending on the mole myosin/actin ratio in reconstituted actomyosin, maximum gel strength occurred in the pH range of 5.5-6.0 . A similar optimal pH value was also reported in hake actomyosin gelation (Beas et al, 1988). Gel strength in both actomyosins underwent a sharp decrease at pH values >6.0.…”

“…Irrespective of the ionic strength, the rigidity of actomyosin gels from mature squids was higher than that from immature squids. A previous work showed that actomyosin from postspawned hake has higher values of both myosin/ actin ratio and rigidity modulus than that from prespawned hake (Beas et al, 1988). In this way, the higher rigidity observed in actomyosin from mature squids could be explained on the basis of a higher MHC content in actomyosin from mature squids, which is a consequence of the minor presence of the 160 kDa degradation product in contrast to immature squids (Figure 1).…”

“…Crupkin et al (1988) had reported variations in the myosin/actin ratio in hake actomyosin related to the reproductive cycle of the fish. It had also been reported that these variations in the actomyosin composition of mature hake influenced the gelling properties of the major myofibrillar protein (Beas et al, 1988). In addition, it was also reported that heatinduced gel strength of chicken red myosin is influenced by nutritional stress (Asghar et al, 1984).…”

The effect of improving raw material quality on product quality and operating costs: a comparative study for lean and fatty fish

“…Biochemical, physicochemical, and functional properties of hake stored on ice or frozen storage related to gonadal maturation of fish indicated that change in the actomyosin composition of mature hake is influenced by the metabolic state of the fish associated with its reproductive cycle (Beas, Crupkin, & Trucco, 1988;Roura, Montecchia, Goldemberg, Trucco, & Crupkin, 1990). Pre-spawned fillets stored at )20°C deteriorated more rapidly than post-spawned fillets did, as indicated by the rate of protein solubility, reduced viscosity, and hydrodynamic properties (Montecchia, Roura, Rold an, P erez Borla, & Crupkin, 1997).…”