DEVELOPING AND VALIDATING PROTOCOLS FOR WATERLESS SHIPPING OF LIVE SHRIMP
Shrimp is the number one consumed seafood product in the U.S., with an average annual per capita consumption of four pounds. Over 90% of the shrimp consumed in the U.S. is imported, and the majority of imported shrimp is from farmed, not wild-caught sources. The U.S. has significant interest in developing an aquacultured shrimp industry. Both pond and RAS production of shrimp (marine shrimp and freshwater prawns) have been shown to be technically feasible and commercial enterprises using both systems exist. However, production costs for U.S. growers exceed those of foreign competitors, such as Asia and Central America. The U.S. market value of commodity shrimp is depressed due to the high volume of foreign product available. To support the continued growth of a shrimp aquaculture industry in the U.S., a niche market that commands a significant premium over imported shrimp prices must be leveraged. The live market represents a very promising niche for U.S.-grown shrimp. It is difficult and costly for importers to ship live shrimp to the U.S; hence the live market represents an opportunity for U.S. producers that will experience little-to-no competition from foreign imports.
If shrimp can be shipped live without water weight, significant savings would be realized. Accordingly, studies have been conducted to develop handling and packing methods for waterless shipment of live shrimp (freshwater prawns M. rosenbergii and marine shrimp L. vannamei). After shrimp are harvested the next step is to prepare the shrimp for shipping. This involves (1) anesthetization, followed by (2) packing in chilled, moist packing material, (3) shipping of shrimp in bags with pure oxygen and moist packing material, and (4) receiving. Many experiments have been conducted using marine shrimp. The first variable investigated was the anesthetization rates which included -5, -7.5, and -10 degrees Celsius per hour. The starting temperature was the culture condition (30 degrees Celsius) and the anesthetized temperature was the holding temperature (single temperature representative of shipping conditions in coolers). We found no significant differences in survival rates for rates up to and including -10 degrees Celsius per hour. We also tested various holding temperatures including 10, 12, 15, and 20 degrees Celsius and found the optimum temperature to be 15 degrees Celsius. There are various packing materials that were considered to be packed with shrimp including wood shavings, sawdust, and newspaper. The wood shavings performed significantly better than the newspaper and sawdust. We are currently investigating re-acclimation rates from anesthetized temperatures to holding tank temperatures representative of a distributor or store. Thus far we are finding that fast re-acclimation temperatures (greater then +10 degrees Celsius per hour) are favorable. The optimum combination for waterless shipping of marine shrimp is as quick as -10 degrees per hour anesthetization rate, holding temperature of 15 degrees Celsius with moist wood shavings, up to 24 hours holding time. We achieved nearly 100% survival using these conditions up to 24 hours and we had satisfactory to good results up to 72 hours. Experiments are currently underway for freshwater prawns and results will be reported at the meeting.