Influence of ice storage on ray (raja clavata) wing muscle

Abstract

Determinations of pH, urea, extractable protein (EP), apparent viscosity (AV), water-binding capacity (WBC), hardness (H), Hunter L, a and b values and sensory evaluation (SE) (raw and cooked), as well as microbiological analysis, were used to study the effects of ice storage on the stability of ray (Raja clavata) muscle. Significant changes were found in pH, bacterial growth and sensory assessment (ammoniacal odour and colour) during the storage period. Urea content, EP, AP, WBC (measured as water loss) and Hunter L value (in cooked muscle) decreased significantly. Statistical analyses did not show significant differences in H and Hunter L value (in raw muscle). The decrease in urea concentration can be described as a linear function of the number of microorganisms suggesting the microbiological character of the process. No dependence was observed between pH or number of microorganisms and EP, whereas AP was much more affected and showed a marked dependence on these two parameters treated independently. The results of this research showed that wings could be stored in ice for 9-10 days without causing important loss of quality. The fish was considered excellent up to day 7 and acceptable after 9 days but unacceptable after 11-12 days onwards. Nonetheless, the shelf-life of the ray in the iced state can vary depending upon the initial state of freshness, handling and the biological conditions of the fish. Microbiological analysis, pH, EP, AV, WBC, SE and Hunter L value have been demonstrated to be factors which could be used to monitor the deterioration of ray during ice storage.

Effect of Carbon Dioxide Atmosphere on Microbial Growth and Quality of Salmon Slices

“…Total bacterial count (TVC) was measured according to Pastoriza and Sampedro (1994). Trimethylamine 348 (TMA) was determined by the method of Dyer (1945) and expressed as mg TMA-N per 100 g. Total volatile bases (TVB) was determined according to Lucke andGeidel (1939, as modified by Antonacopoulos (1960), and expressed as mg TVB-N per 100 g. Measurements of pH were carried out in a sample homogenised with water (ratio 1 : 2).…”

Effect of high-pressure treatment on processing quality of tilapia meat fillets

“…triglyceride) content. Neutral lipids have the capacity to dissolve free fatty acids and to neutralize their hydrophobicity, which exerts desolubilizing effect on the proteins (De Koning, Milkovitch, & Mol, 1985;Pastoriza & Samperdro, 1994;Srikar & Reddy, 1991). Free fatty acids and fatty oxides interacted with protein surface to form hydrophobic regions and decreased the extraction of proteins (Sikorski, Olley, & Kostuch, 1976).…”

Efeito do gelo clorado sobre parâmetros químicos e microbiológicos da carne de carpa capim (Ctenopharyngodon idella)

“…A determinação do pH foi realizada em profundidade conforme descrito por PASTORIZA & SAMPEDRO [25]. A leitura foi realizada em aparelho medidor de pH DMPH -2 Digimed.…”