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Freshly harvested clams (Galatea paradoxa Born) obtained from the Cross River, Nigeria were subjected to live storage for 7 days in or outside of water. The objective was to study the effects of storage method and duration on mortality, weight changes and selected physical and physicochemical properties of the clams. Overall, 62 or 35% of the stored clams died over the 7‐day duration under wet (potable water) or dry storage, respectively. No deaths were recorded in day 1 (wet storage) or in days 1–3 (dry storage). Regression analysis showed linear relationships between storage duration and each of the dependent‐quality variables of weight change, density, pH and electrical conductivity (EC) evaluated under both storage methods. The regression coefficients (β1, β2) for assayed quality parameters in wet or dry storage were significantly different (P ≤ 0.05). R2were generally larger for dry storage than for wet storage. Initial clam weights did not significantly (P ≥ 0.05) affect weight change during storage, indicating that weight loss during dry storage was statistically invariant with clam weight. The study concludes that priority should be given to prompt sale and utilization (<3 days) of clams, particularly large clams. The use of dry storage to reduce postharvest mortality and weight losses will potentially increase the profitability of the clam industry.

Samples (n= 100) of freshly harvested clams (Galatea paradoxa Born) from the Cross River, Nigeria, were subjected after 24 h depurations to heat treatment (steam and water at 60, 70, 80, 90, 100C) for 1–6 min to evaluate the effects of level of heat treatment on opening, meat yield, sensory properties, proximate composition, pH and electrical conductivity (EC). Observations were also made on the effects of some chemical shucking aids (NaOH, NaHCO3, Na2CO3, NaCl) in 60C water on these parameters. Results showed that boiling water was most effective in opening the clams, with 100% shucking achieved in 1 min. Steam was least effective, requiring 6 min for 100% opening. Temperature significantly and strongly influenced meat yield (p<0.05;r=‐0.92). pH (p<0.01; r=0.97), EC (p<0.05; r =0.65) and sensory properties (p<0.05). In general, shucking aids reduced opening time, significantly p<0.05) raised meat pH and EC, and with the exception of NaCl, insignificantly (P>0.05) improved yield. NaHCO3, and Na2CO3, which cut time for 100% opening from 5 min to 2 min were most effective. There were slight but significant (P <0.05) drops in meat moisture, crude protein and ash contents with increase in temperature (T). the model equations, pH = 4.69 + 0.021 T and % yield = 39.95–0.172 T were found to reliably predict meat pH and yield, with insignificant differences (P>0.05) between predicted and experimental values.

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