EVALUATION OF GRADING, DEPURATION, AND STORAGE TIME ON CRAWFISH MORTALITY DURING COLD-STORAGE

Red swamp crawfish (Procambarus clarkii Girard) were subjected to thre e postharvest treatments (grading, grading and purging, or no addition al treatment) and three cold storage (4 +/- 0.2-degrees-C) periods (2, 4, or 6 days) in a factorial arrangement to determine the effects of these factors on crawfish mortality during cold storage. Significant d ifferences were observed for both main effects. Mean mortalities durin g cold storage were 10.5, 10.3, and 19.5% for the control, graded, and graded/purged groups, respectively. Mean percentage loss of 7.8, 10.8 , and 21.7% were observed for the 2-, 4-, and 6-day periods of cold st orage, respectively. Crawfish that were graded and then purged for 24 hr and crawfish held for 6 days in a cooler had significantly higher m ean mortalities during cold storage. An additional mean mortality of 1 1.6% was observed during the 24-hr purge period. Overall, mortality lo sses were generally highest early in the harvest season and declined o ver time. Results from this research demonstrate that substantial loss can occur both during and after the purging process and present evide nce to rebut the idea that purging may be beneficial in increasing the shelf life of crawfish during cold storage.