Across south eastern Australia, an estimate of over 20,000 tonnes (approx. 20 million kilograms) of fish waste is produced each year. Seafood markets such as our local Sydney Fish Markets, generally only keep the fillets during the processing of fish. This means the remaining two thirds of the whole weight, consist of fish heads, guts, bones and skin, gets discarded. In some cases, this waste may be transported from the processing site to get rendered, however it is usually discarded to landfill. As a result, these industries are copping major backlash for inadequate disposal systems because such wastes cause environmental problems (Arvanitoyannis & Ladas, 2008) and is becoming increasingly costly for the whole industry as it costs the processor up to $150 per tonne.
As a possible solution to better manage and improve the utilisation of fish waste being left unwanted, seafood industry leaders discussed at a Fisheries Research and Development Corporation (FRDC) workshop in 2001 particular techniques to process the waste into products such as aquaculture feeds (food specially formulated to contain all essential nutrients for seafood consumption), silage, fertilisers, fish mince, and fishmeal. After careful consideration the leaders agreed to produce fish-based fertiliser from the fish waste as it was the most feasible option during that time. This was the most suitable option as it would utilise the bulk of the fish waste and it is proven to be cost-effective due to the low volume and wide geographical area covered by Australia’s seafood industry. From the article, ‘Utilisation of seafood processing waste – challenges and opportunities’, Ian Knuckey writes, Australian Seafood Co-products (ASCo) Fertilisers intend to potentially use large quantities of fish-based fertiliser on farming sectors for agricultural crops and can also be certified for use in the rapidly growing organic (farming) market.