Quality of Whole Lobster (Homarus americanus) Treated with Sodium Tripolyphosphate Before Cooking and Frozen Storage

The objective of this study was to determine the effects of pre-rigor treatment of lobster muscle with sodium tripolyphosphate (STP) before cooking, cryogenic freezing, and frozen storage. STP concentrations of 0.1% and 0.3% were prepared in 0.9% saline solution and injected into lobster before processing. Controls were injected with 0.9% saline solution. Lobsters were then steam-cooked, cryogenically frozen, and stored at −15 °C. Chemical and textural analyses were conducted on reheated samples at storage months 0, 2, 4, and 6, and sensory analyses were conducted at months 2 and 6. Cook loss results showed the 0.3% STP-treated lobsters had a 5% significantly (Pleqslant R: less-than-or-eq, slant 0.05) lower cook loss than the 0.1% STP and control samples. Yield results revealed that STP-treated tails had a 0.7% to 0.8% significantly (Pleqslant R: less-than-or-eq, slant 0.05) higher meat yield than control samples. Total moisture results showed that STP-treated lobster tail and claw meat had higher total moisture levels compared with control samples at month 6. Sensory results revealed that panelists rated both 0.1% and 0.3% STP-treated lobster tails significantly (Pleqslant R: less-than-or-eq, slant 0.01) higher for flavor and texture, and significantly (Pleqslant R: less-than-or-eq, slant 0.001) higher for overall acceptability than control samples at month 6. The results indicated that STP added at low concentrations may extend the shelf life of whole cooked cryogenically frozen lobster, decrease lipid oxidation over frozen storage time, maintain texture, color, and flavor attributes, increase yield, and decrease drip loss.