Giant Freshwater Prawn Supplier: Head-On, Headless and Peeled, IQF or Block

Product overview

The giant freshwater prawn is the big-clawed river prawn of Thai, Bangladeshi, Indian and Malaysian cooking: grilled whole over charcoal, simmered in coconut curries or baked in a clay pot with glass noodles. It is a different animal from the marine shrimp that dominate the frozen trade, growing in fresh water and carrying a large head, long claws and a sweet, softer-textured tail. Buyers who know it order it by name, and the head-on prawn is a menu feature in its own right, which is why the head and claws need as much care in processing as the tail.

Macrobrachium rosenbergii is farmed in earthen ponds across South and South-East Asia. Thailand has a long-established farming sector that supplies both domestic buyers and export packers, and partner origins include Bangladesh, where the prawn is known as golda, India, Vietnam and Malaysia, while China is a large producer for its home market. Each offer gives the country and farm area. Trade names need care: in India the species is often sold as scampi, a word that UK and many European buyers reserve for Nephrops norvegicus, the langoustine, so labels and invoices carry the scientific name to keep the two apart.

Formats are head-on shell-on (HOSO), headless shell-on (HLSO) and peeled, either peeled and deveined (PD) or peeled undeveined (PUD), frozen IQF or in blocks. Head-on prawns are graded by pieces per kilogram, for example 6/8, 8/12, 13/15 and 16/20, with larger grades in limited supply, and headless and peeled product by count per pound or kilogram. Because the head and claws make up a large share of body weight, especially in mature blue-claw males, a headless or peeled count moves much further from the head-on grade it came from than it would in marine shrimp, and tail yield per kilogram of whole prawn is lower than for marine shrimp of similar size. Our guide to frozen shrimp count, glazing and net weight shows how these figures interact.

Freshwater prawns need fast handling. Digestive enzymes from the head can soften the tail meat if the prawns are not chilled and frozen promptly, giving the mushy texture buyers complain about, so packers are asked to ice-chill at harvest and freeze without delay. Lot checks, arranged on request, cover black spot and darkened heads, loose or dropped heads, broken claws and legs, soft shells from recent molting, an earthy or muddy taint, count accuracy and glaze. Any sulfite used against black spot is declared, and farmed lots can be tested for veterinary drug residues against your destination’s limits. For marine species in the larger counts, see large shrimp and prawns.