New Modified Dipping Method Using 4-hexylresorcinol for Preventing Blackspot Formation in Prawns

• Published in: Journal of aquatic food product technology Vol. 18; no. 3; pp. 284 - 293
• Main Authors: Slattery, Steven L., Williams, David J., Torrisi, Caterina
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 26.06.2009
• Subjects: 4-hexylresorcinol; blackspot; dip; melanosis; prawns; residues; yield
• DOI: 10.1080/10498850902762299
• ISSN: 1049-8850

Industry acceptance of alternative sulphite treatments for preventing blackspot in prawns is limited. This study demonstrated that dipping prawns (Penaeus monodon and Fenneropenaeus merguiensis) in a less concentrated solution for longer times provides better control of blackspot formation than the recommended 2 minute dip in 50 mg/L 4-hexylresorcinol. Protection improved as modified dipping times and solution concentrations increased. Blackspot protection provided by most of the modified dip methods was more effective than a 1 minute dip in 1% sodium metabisulphite. The recommended 2 minute dip method should be limited to 125 kg when used on consecutive 25-kg batches of prawns. Yields increased by less than 10% even after 72-hour exposure in the modified dip. The new dipping method meets most international residue standards when applying the modified treatments evaluated.