ITI develops low cost animal feed from fish waste

Researchers at the Food Technology Division of the Industrial Technology Institute (ITI) have developed a protein rich low cost feed / feed ingredient for pigs using fish waste.

This value added product known as fish silage was prepared via a chemical process where the fish waste is converted into thick slurry by totally solubilising the tissues resulting in a homogeneous feed.

The fish silage so prepared has several advantages. It is a protein supplement for livestock, especially for pigs and as the proteins are present in a partially hydrolysed state it is easy to digest and absorb. The silage also acts as a chemo-attractant (feeding stimulant) due to the high amount of free amino acids. Additionally the product has a shelf life of about two years and will not putrefy under existing conditions in local piggeries.

One of the most interesting characteristics of the product is that it has a malt odour rather than the fishy smell and it requires no pre-heating. The fish silage can also be used as an ingredient for poultry and fish feed.

Silage was first developed in 1920s for the preservation of fodder. The technique was then applied to fish waste in 1940 and Denmark is the first country to produce fish silage on a commercial scale.

Fish silage was experimented in Sri Lanka in 1955 and again in 1980 purely for research purposes.However, the research conducted by the Industrial Technology Institute (ITI) was aimed towards commercialisation from the very beginning. The research was initiated in 1999 when the Ministry of Fisheries of the Western Province requested the Institute to address the issue of fish waste, especially shark heads and viscera.

The ITI research team comprised Senior Research Officer Dr. (Mrs.) Yasmina Sultanbawa (leader), S. S. K. Madage, S. Rajapakse, R. A. P. Perera and D. Medis. The team has already been awarded patent rights for the process for manufacture shark silage.