Louisiana Gulf Coast oysters (Crassostrea virginica) were subjected to thermal shucking treatments to effect adductor muscle release from both left and right valves. The oysters were instrumented with thermocouples to monitor and record process temperatures in the oysters and on the shell. Following treatment, the oysters were evaluated for relaxation and release of the adductor muscle, meat quality and texture, and for the effect of the treatments on the storage life of the oysters as measured by total microbial plate counts. The treatments of many oysters resulted in a complete release of the adductor muscle from the shell while maintaining a quality raw product. One of the most promising treatments was a 60 second steam injection followed by a 60 second hold time and 120 seconds of ice water bath. This treatment proved exceptional overall with shelf stability over 14 days, an overall Average Release Value of 1.18 and an overall Quality of 1.86, both of which are good. A second treatment consisting of a 15 second pre-heat followed by a 45 steam injection, no hold time and 4 minutes of ice water bath resulted in an overall Average Release Value of 0.33, which is excellent, and an overall Quality of 2.10 which is very close to acceptable. Sixty-seven percent of the oysters subjected to this treatment were considered successfully shucked based on degree of release and quality. Processing did affect the texture of the oysters but seemed to have little overall effect on storage life. This low-pressure steam process shows promise as an effective, low-cost alternative to current, high pressure commercial oyster shucking processes.
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