BioCycle November 2004, Vol. 45, No. 11, p. 67
Using clean manufacturing technologies from European researchers, fish skins are processed into leather for use in handbags, belts and shoes.
Gareth Evans

FISHING AND FASHION hardly seem natural partners in the best of times, but the idea of these industries uniting in a novel approach to organics recycling sounds decidedly unlikely, to say the least. However, first impressions aside, that is exactly what happened when a small Spanish fish processing company, Pinchomania, joined forces with INESCOP, the Spanish Institute for Footwear and Leather, to address the problem of waste fish-skins, by turning them into shoes.
The scale of this waste problem is surprising – smokeries discard more than 300 tons of salmon skin every year in Spain alone and across the whole of Europe, thousands of tons of skins enter the waste stream annually. With the European Landfill Directive establishing a significant brake on the amount of biodegradable waste entering traditional disposal routes, the fish processing industry faced a major dilemma.
Pinchomania found that their own contribution to the problem routinely amounted to around 2,000 skins daily. Having successfully completed a series of preliminary experiments with tanning the skins, the Malaga-based company contacted INESCOP to see if there was scope to explore the idea further.
By a fortunate chance, Cocinados Gimar – another Spanish smoked-salmon producer – was also trying to find a solution to the same waste management question. They had come across INESCOP at a workshop organized by the European Commission to encourage participation in its funded research and innovation projects.
The early work had established that, if properly treated, fish-skin could be used to make leather goods in just the same way as reptile skins. Waste salmon skins are particularly suited to tanning because the fish themselves are relatively large and the smoked salmon produced tends to be sold in sizable portions. Both of these facts mean that the discarded skins are available in fairly big, undamaged pieces.
EUROPEAN FUNDING
Though the fish smokers had the raw material, and a vested interest in the success of the idea, they lacked the resources to make it happen. Enter the Cooperative Research Project program (known by the acronym CRAFT), designed to make European Union funding available to smaller companies. CRAFT specifically enables groups of two or more such firms facing similar technical problems to hire external researchers to overcome their lack of in-house R&D capacity.
ESCOP was ideally placed both to find suitable industrial partners and also to look after the project management, which was to be a vital first step in attracting CRAFT funding. Three new partners joined the group: Tradelda, a tannery, and the two leatherwear manufacturers, Zapatos Ricardo’s and Borse, bringing essential expertise to the team.
It was fairly obvious, however, that turning waste fish skins into a valuable leather had potential applications far beyond Spain. INESCOP is a member of EURIS, a group of technology centers from nine EU countries, with particular interest in the leather industry. Having brought the fledgling project to their attention, three research centers, in France, Italy and Greece, joined together with a second tannery, the French Tannerie de Callac. Two Greek leather goods manufacturers, Mandigora Grigoris and Lianos Panagiotis, and the Italian shoemaker, Calzaturificio Santa Maria, completed the final line-up.
ENVIRONMENTAL ISSUES
While dealing with the waste issue was of fundamental importance, another major consideration soon emerged from the discussions. With the underlying drive based firmly in European environmental legislation, there was something of a contradiction in the (then) available methods of pickling and tanning, which were time-intensive, required huge quantities of water and used chemicals which if not toxic, could hardly be described as environmentally friendly. For the project to succeed, it needed first to address these issues.
The production of leather has traditionally been a very competitive area and process changes have inevitable cost implications associated with them. However, as effluent treatment becomes increasingly heavily regulated, and expensive, the use of clean manufacturing techniques brings its own benefits, both to the balance sheet and the public image of the industry. One of the essential conditions of European-funded research projects is that all the collaborators should ultimately benefit and so much of the initial focus of this project lay in developing novel approaches to tanning, pickling and degreasing.
Ultimately, a new method of curing the skins that is both commercially and environmentally viable was developed. Water consumption was reduced by 60 percent, the processing time cut from 14 days down to just five, and the use of chemical agents vastly reduced. Salt has been completely eliminated from the pickling stage and the demand for amines and sulfur-containing compounds reduced to little more than a quarter of previous levels.
A further problem that the researchers had to overcome, and one which was fundamental to the new leather’s acceptance, was its lingering fishy smell. The solution adopted – the use of biodegradable degreasing agents – benefited both the product and the environment. Traditional degreasing procedures produce significant amounts of both airborne volatile organic carbons (VOCs) and surfactants. This new, enzyme-based approach significantly reduces these, not only giving better results in terms of consistent quality, superior dye uptake and final color, but also opens the way for water-based natural finishings to be used. The end product can withstand temperatures in excess of 90°C (194°F) and is resistant to scuffing or scratching.
With the fundamental problems in pickling and tanning the skins successfully overcome, the next step was to begin production and quality control trials. An initial batch of two thousand fish-skins underwent the process, split equally between the participating French and Spanish tanneries. This pilot scheme produced leather on a commercial scale, which was then finished in a variety of colors and made into a wide range of shoes, bags, wallets and belts for comparison with more conventional and established products.
ENTERING THE MARKET
By the time the two-year CRAFT project finished, everyone involved was delighted with the results. The fish processors had an alternative disposal avenue and one which promised them potential revenue from their waste; the tanners had exclusive rights to an innovative process and a new product line; and the manufacturers had gained access to a novel and select material. In addition, buyers were presented with fashion items made in an environmentally friendly way, from a product which was previously considered waste. The benefits were clearly tangible and the potential market is world-wide, particularly since Italy and Spain are the world’s largest exporters of leather shoes, with long established global lines of distribution.
In addition, the curing techniques themselves also have commercial value. Since one of the factors in achieving the high quality of the leather produced is to treat the skins while fresh, technology transfer to local companies is more sensible than attempting to export skins for treatment elsewhere. Interest in licensing the process was quick to materialize from Asia and South America.
Next, the true market position of “cuir de mer”, as the product was being called, had to be established. The first real clue came when, after hundreds of pairs of shoes had been manufactured from cuir de mer in a wide range of colors, styles and designs, the first samples were unveiled at the Italian Leather Fair. They were very well received and a number of manufacturers voiced their interest in the new product. “The reaction was amazing,” says Enrique Montiel of INESCOP, coordinator of the original CRAFT project.
After the show, several commercial agreements were struck between firms in France, Italy, Spain and Chile to start the fish-skins’ journey into the mainstream of fashion. The transition is not likely to be an easy one, however. While there is a clear potential market, it is not easy for new products to break into it. Footwear manufacture accounts for 80 percent of the leather produced in Europe and other materials, such as plastics and textiles, are already well established.
Curiously, the relative scarcity of the salmon-leather – it takes two fish to make enough leather for just one shoe – coupled with the original “waste” nature of the raw material, may ultimately be the key to its commercial viability. While the consumer buys an unusual, eco-friendly product, shoe manufacturers have a unique, premium material, which delivers high quality at an attractive price. Since the supply is never likely to be large compared with traditional materials, the argument goes, the market should never be saturated. Certainly, the fashion industry is renowned for its love of anything novel and exclusive.
“Fashion is a fickle thing”, Montiel comments. “In footwear, it changes on a four-month cycle. Our industry has to try to be predictive – guess what will be the next ‘in-thing’ months ahead of manufacture.” So, while he is excited by the future of cuir de mer, Montiel also knows that at least some of the initial interest is by way of a reaction to the current return to popularity of reptile skins. He remains positive about the product, but freely admits its true market share is unlikely to become finally clear much before the end of the 2004/5 season.
Obviously it is far too soon to assess the project’s long-term benefits, either economic or environmental. The original consortium has been joined by ten more companies keen to assist in the commercial exploitation of the material and method, which certainly seems a healthy sign. Whatever the eventual outcome, the venture stands as a prime example of just how innovative organics recycling can be, and how lateral thinking can take a material out of waste bins and the beaks of squabbling seagulls, to the high-fashion catwalks of Milan.
Based in Scotland, Gareth Evans is a freelance writer and environmental consultant, as well as author of “Biowaste and Biological Waste Treatment.”