The Fisheries Sector in the Caribbean Community is an important source of income. Four Caribbean countries have done an inventory of the major sources of mercury contamination in their islands. Credit: Desmond Brown/IPS
 

NAIROBI,  Nov 28 2018 (IPS) – There’s a woman out there making gelatin from fish scales, don’t you know?

She’s helping herself to handfuls of discarded fish scales – tilapia and Nile perch – and working sweet science to extract gelatin from them.

Globally, we get through as much as 400,000 tonnes of gelatin a year – it’s in protein supplements for body-builders, old-school camera film, as a texturiser for processed foods. Almost half of it is rendered from pig skins; the rest is extracted from bovine hides and bones. Two percent is produced from fish – the difficulty with gelatin from fish.

So our gelatin maker: she takes discarded scales. She washes them. She dries them. Then she soaks them in hydrochloric acid for a day. Washes and dries, then soaks it in lye – sodium hydroxide – for another day.

Then it’s ready to be heated up to 80 degrees Celsius for an hour, so the gelatin can be filtered out. She’s worked out that three-minute bursts of ultrasonic irradiation (sound at a frequency higher than humans can hear) during the heating of tilapia scales made it significantly stronger. (But not the perch scales, for whatever reason.) Then she puts cools it in a chamber at 5 degrees.

And there she is with gelatin – at this stage, her output is a little weaker gel than she’d like. It melts at a lower temperature than would be ideal, but it’s perfect as, say, a protein enhancement for fish food, or as an additive to thicken sauces.

It’s so clever: producing gelatin from a raw material available for nearly free. The materials are readily available – and avoid the need for expensive enzymes like pepsin that are used in traditional gelatin production. The heat extraction process is short and easy. The method can readily be adopted by small-scale processors.

Alice Mutie is our gelatin wizard’s name. She’s doing her research under the auspices of the Kenya Marine and Fisheries Research Institute and Nagasaki University’s Graduate School of Fisheries and Environmental Sciences. Part of a new generation of sharp young scientists applying science to creating value in places no one was looking.