2011/746 Value adding to the School Prawn Industry: Clarence River case study

By Karen McNaughton

School prawns (Metapenaeus macleayi) are marine and estuarine prawns found along the east coast of Australia, between southern Queensland and eastern Victoria. Given that school prawns are low to medium priced, there is significant opportunity to increase the margin for this species by value adding. Due to the small average size of school prawns, it is not possible to produce a peeled product with current technology, but there is an opportunity to extract prawn meat from whole prawns.

This project investigated the production of an extracted school prawn meat from green and cooked prawns. The prawns were processed in a Baader separator which squashed the soft tissue (prawn meat) into a perforated drum. The extracted products were collected, packaged and the shelf life assessed through sensory, microbiological and biochemical methods.

The Baader separator was successful in extracting and recovering cooked prawn meat. Vacuum packaging and freezing the cooked extracted meat appeared to provide adequate protection against product degradation during storage. Cooking the prawns prior to extraction helped to stabilised the product. The market feasibility of the cooked extracted prawn meat was evaluated by determining the products indicative cost, potential and likely usage, and seeking feedback from respected food manufacturers.

The presence of grit (sand) in the extracted meat was identified as a barrier for use as an ingredient in mixtures and fillings; the meat had potential to be used in the manufacture of a number of liquid based products, namely soups, stocks and sauces. A number of liquid based products were manufactured using the extracted cooked prawn meat as a key ingredient. Two stocks and two soups were prepared and evaluated by product development staff at a number of targeted food manufacturers, who generally rated them highly.