Shrimp is marketed in many forms: shelled or unshelled, raw or cooked, and fresh or frozen. Raw shrimp should smell of ocean, with no hint of ammonia. Cooked, shelled shrimp should be plump and firm. Fresh, uncooked shrimp should be cleaned under cool water and drained.
Frozen shrimp is more popular among the consumers. Frozen shrimp is less expensive than fresh one. Frozen shrimp is sold packed in packages of 15 lb, 5 lb, 2lb and other sizes. In supermarkets and malls frozen shrimp are also sold by weight.
Before shrimp becomes frozen it should be caught and some species of shrimp should be raised. For that purpose there are shrimp farms. Farm raised shrimp has a fair market price compared to the quality and taste of wild harvested shrimp. Even pacific white shrimp is offered nowadays by shrimp farms. Consumers find pacific white shrimp to have the best aroma, appearance, flavor, texture and more moisture compared to wild harvested shrimp. Farm shrimp is raised under stringent environmental controls in compliance with the applicable standards and is tested and certified.
Shrimp is primarily caught with bottom trawls. Additional types of fishing gear include butterfly nets, beam trawls and bag nets. Then shrimp are immediately packed in ice and delivered to a processing facility. Shrimp arrive at the processing facility and are immediately placed in a staging cooler. The temperature in this cooler is held close to, but not at, freezing to keep the shrimp as fresh as possible without actually freezing them prior to processing. Shrimp are graded, which refers to the process of examining the shrimp for size and quality. Shrimp not meeting quality specifications are rejected. Frozen shrimp is processed and sold in many ways, including removal of the head, shell (peeling), vein (deveining) and tail. Shrimp to be sold in various processed states are delivered to processing lines designed to perform these activities. Some shrimp are processed by machine; however, frozen shrimp are generally large enough to be processed by hand. For added convenience, some frozen shrimp are sold pre-cooked. Shrimp to be sold cooked are sent to large boiling tanks, which are operated within specified temperatures and cook time. Cooked shrimp are cooled quickly to maintain quality. After grading, processing and/or cooking, shrimp are placed on a sterilized conveyer belt and sent through a quick-freezing tunnel. This process is known as IQF (individual quick freezing). Shrimp emerge from the IQF tunnel and are immediately placed in airtight bag pouches. The bags are sealed and packed in master cases, which are immediately delivered to cold storage (a refrigerated warehouse where product is kept in a frozen state). Samples of each finished production code receive qualitative (e.g., color, odor, flavor, texture and cleaning) and quantitative evaluations prior to being released for shipment. Finished product is shipped or staged in cold storage for later shipment.
This is the way shrimp is caught, frozen and shipped to supermarkets to find its consumers and become a tasteful dish or snack. As you see it is not the process of one day.