Effects of Rigor Mortis on Gel‐forming Properties of Surimi and Unwashed Mince Prepared from Tilapia

Abstract

MATERIALS & METHODSQuality of surimi and unwashed fish (tilapia, Areochrumb aureus) mince was investigated as affected by development of rigor mortis in fish prior to processing. Significantly higher protein content and yield, reduced cook loss, and enhanced gel-forming ability and protein extractability were associated with surimi produced from pre-rigor fish. Gels prepared from unwashed minced muscle exhibited less cook-loss pre-rigor, but stage of rigor had little effect on gel rheological properties and protein extractability. Thermal rigidity scanning and differential scanning calorimetry showed substantially higher rigidity values and enthalpies of denaturation, respectively, for surimi prepared from pre-rigor fish, but no effect on transition temperatures due to stage of rigor. Sample preparationThe fish used for this study were blue tilapia (Areochromis aureus), obtained from AB Limited (Raleigh NC) and held as described by Korhonen et al. (1990). Fish were gently removed from tanks and immediately sacrificed by insertion of a knife blade into the brain.

Protein Changes Caused by High Hydrostatic Pressure (HHP): A Study Using Differential Scanning Calorimetry (DSC) and Fourier Transform Infrared (FTIR) Spectroscopy

“…They observed that during the rigor process the denaturation endotherms of muscle proteins generally remained unchanged. On the other hand, a substantial decrease in denaturation enthalpy of surimi prepared from prerigor Tilapia fillet as compared with postrigor Tilapia fillet that was also reported by Park et al [31]. Changes in the protein thermal profile in the postrigor state can be attributable to the biochemical, metabolic, and microbiological changes experienced by the muscles during the rigor resolution stage (Buckow et al 2013).…”

The effect of low‐ or non‐sweet additives on the stability of protein functional properties of frozen cod surimi

“…Although in each study fillets were obtained as fresh as possible and the methodology was similar, other factors such as fish age, origin, season of catch, reproductive cycle (pre-and postspawning) and state of rigor mortis might account for some of the variation among batchs in initial protein solubility (Lee, 1985;Beas et al, 1988;Park et al, 1990). Park et al (1990) recently noted a significant decrease in surimi protein extractability and protein enthalpies during successive stages of the development of rigor mortis for tilapia. These researchers suggested that protein denaturation in surimi might be promoted by factors involved during the development of rigor mortis in fish muscle, such as low muscle pH (Park et al, 1990).…”

Elaboration of sausage using minced fish of Nile tilapia filleting waste

“…The development of new products elaborated with MF, which yet retains all the nutritional advantages of the fish, might be a way of increasing the intake of this animal protein, besides adding value to the products generated by the Brazilian aquaculture. Some studies have already been carried out utilizing the whole eviscerated tilapia for obtaining the MF (Gryschek et al, 2003) and surimi (Park et al, 1990). Other fish species have also been used for MF and elaboration of products, such as the silver carp, Hypophthalmichthys molitrix (Hu et al, 2008), trout, Oncorhynchus mykiss (Setiady et al, 2007) and catfish, Clarias anguillaris (Negbenebor et al, 1999).…”