51A-1

C. S. LIN, Y. -. C. Hung, and C. -. M. Park. Department of Food Science and Technology, University of Georgia, Center for Food Safety and Quality Enhancement, 1109 Experiment street, Griffin, GA 30223

Shrimp is one of the most popular seafood items served in restaurant. Frozen shrimp is the most common form of material used by restaurant to prepare their shrimp dishes.

This study was designed to evaluate the quality and safety of shrimp thawed using a constant temperature-thawing chamber.

A constant temperature chamber which can maintain the temperature at 5 °C (FWE chamber) was used for this study. The temperature profile of the thawing chamber as well as the shrimp blocks during thawing were monitored using a Hotmux data logger equipped with T-type, 30 gauge thermocouples. Running water thawing was used to compare with the FWE thawing. Shrimp thawed in room temperature air was used as the control. All quality evaluations including drip loss, yield and moisture content as well as press juice and shear force were conducted within 2 hr after thawing. The aerobic plate count of samples was also determined. The whole study was triplicated.

The FWE chamber maintained the temperature at 5 °C throughout the study. The FWE chamber can also provide a more uniform thawing than water thawing. Shrimp thawed using the FWE chamber had a lower drip loss, higher yield and moisture content than shrimp thawed by running water. However, the differences were not statistically significant. There were also no significant differences on press juice and shear force between control and shrimp thawed using either running water or FWE chamber. However, aerobic plate count results indicated that shrimp thawed using the FWE chamber had lower bacterial count than both control and shrimp thawed using the running water.

Results obtained from this study suggest that quality and safety of shrimp thawed using a constant temperature thawing chamber were better maintained than room temperature and running water thawing processes.