Finding a replacement to the commonly used metabisulphite preservative is high on the ACPF’s investment list.

Trials indicate that species differences in melanosis development occur with all treatments. A number of small scale controlled on-board trials have shown PrawnFresh is effective but has different effectiveness between the species, including optimal concentration and dipping times.

The project team is working with a number of individuals doing additional targeted on-board work to better understand and confirm species and operational differences in effectiveness, and later provide guidance around optimal concentration, usage rates and dipping times. New vessel case studies are very welcome.

Results to reduce blackspot at 3 days from catch are showing:

On-board trial – Eastern King Day 3

On-board trial – Eastern King Day 3

Prawnfresh showed early stage comparable results (at 1.25ml/L for 3min – 25% higher than the manufacturer rates) to Meta (at manufacturer rates) for Eastern kings.

On-board trial – Endeavour Day 3

On-board trial – Endeavour Day 3

PrawnFresh showed early stage comparable results (at 1.25ml/L for 3min – 25% higher than the manufacturer rates) to 16.75g/L Meta (at manufacturer rates) for Endeavours.

On-board trial – Brown Tiger Day 3

On-board trial – Brown Tiger Day 3

PrawnFresh showed early stage comparable results (at the 1ml/L manufacturer rates) to Meta (at half strength) for Brown tigers.