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Technical Assistance to Encourage More Production and Utilization of Post Harvest Processed Oysters (PHP) Post harvest processing (PHP) methods to reduce potential microbial pathogens in raw oysters have been developed, scientifically validated, and implemented in commercial operations located in coastal states across the Gulf of Mexico. The methods employ thermal intervention with heat and/or freezing, or exposure to high pressures designed to eliminate or significantly reduce the targeted microbial pathogens, Vibrio vulnificus and Vibrio parahaemolyticus. Although these current commercial responses have been proven to reduce the pathogenic Vibrios, persistent illnesses exceed the stringent goals established by FDA. Reasons for failure include: Need to expand commercial use of PHP both in terms of the number of commercial operations and volume of product used across regions and seasons; Increase market use, acceptance and preference for PHP products; and Lack of thermal controls at point of harvest. The proposed work intents to increase PHP oyster processing and product utilization via: Providing value-added approaches to existing and new PHP processes that rely on freezing and frozen storage or irradiation as the primary controls to reduce Vibrio bacteria. Improving PHP efficiency and reducing operating costs through alternative uses of the equipment during seasons with limited oyster production. Revising and implementing HACCP programs for PHP options to assure the operations are in compliance with the latest regulatory mandates. Investigating alternative harvesting practices that can prevent elevated growth of Vibrio bacteria, particularly Vibrio parahaemolyticus, prior to placement in refrigeration.
NON-TECHNICAL SUMMARY: Post harvest processing (PHP) methods to reduce potential microbial pathogens in raw oysters have been developed, scientifically validated, and implemented in commercial operations located in coastal states across the Gulf of Mexico. The methods employ thermal intervention with heat and/or freezing, or exposure to high pressures. All methods were designed to eliminate or significantly reduce the targeted microbial pathogens, Vibrio vulnificus (Vv) and Vibrio parahaemolyticus (Vp). These naturally occurring bacteria have been associated with illnesses and deaths due to consumer preferences to consume raw oysters. The PHP methods provide options to continue commercial production of raw oysters that can be denoted as safer. Regulatory and public concern for persistent illnesses due to consumption of raw oysters, particularly for consumers at risk due to compromised health, culminated in federal mandates to increase commercial PHP capacity and reduce raw oyster-borne illnesses. Commercial response has exceeded the mandated `PHP capacity" goal through 2006 and reduced Vv illnesses below the goal set for 2006, but preliminary indications suggest documented Vv illnesses will exceed the `60% reduction' goal set for December 2008 (VMC, 2008). Likewise, additional regulatory concerns for probable illnesses due to Vp have recently introduced new mandates focused on more controls for Vp. The Vp measures call for more PHP methods and additional controls at harvest. All federal mandates are calling for more PHP to provide safer raw oysters. Although the current commercial applications have been proven to reduce the pathogenic Vibrios, persistent illnesses exceed the stringent goals established by FDA (U. S. Food and Drug Administration) in company with the ISSC (Interstate Shellfish Sanitation Conference). Reasons for failure include: Need to expand commercial use of PHP both in terms of the number of commercial operations and volume of product across regions and seasons; Increase market use, acceptance and preference for PHP products; and Lack of thermal controls at point of harvest. More restrictive controls may include abandoning raw oysters for production of oysters just "For Cooking Only" or actually stopping oyster harvests for half-shell, raw consumption. To avert these adverse commercial consequences, additional and supplemental responses are necessary to satisfy concerns for illnesses reduction due to consumption of raw oysters in the USA. <P>APPROACH: Providing value-added approaches to existing and new PHP processes that rely on freezing and frozen storage or irradiation as the primary controls to reduce Vibrio bacteria. Improving PHP efficiency and reducing operating costs through alternative uses of the equipment during seasons with limited oyster production. Revising and implementing HACCP programs for PHP options to assure the operations are in compliance with the latest regulatory mandates. Investigating alternative harvesting practices that can prevent elevated growth of Vibrio bacteria, particularly Vibrio parahaemolyticus, prior to placement in refrigeration.