Uptake of Sodium and Phosphorus, and Weight Changes in Prerigor Cod Muscle Dipped in Sodium Tripolyphosphate Solutions

Abstract

The uptake of sodium and phosphorus and weight changes in small samples (ca. 10 g) of prerigor cod (Gadus morhua) muscle dipped in sodium tripolyphosphate (Na₅P₃O₁₀ 6H₂O) solutions have been measured. These parameters were studied as a function of solution concentration for a constant dipping time of 2 min. The uptake of solution and quantity of drip produced on thawing decreased between 0 and 7 hr postmortem, partly compensating one another leaving the final muscle weights the same for the two periods. Calculations show that the additional sodium and phosphorus in the muscle after dipping and after freezing and thawing to be in the same ratio as that in solution, indicating that the Na₅P₃O₁₀ molecule remains intact during processing under the conditions used here. About 260 moles of water per mole of Na₅P₃O₁₀ are retained in the muscle after freezing and thawing.