Animal skins as a source of high-quality protein and fats

Almost all Dutch tanneries have had to close their doors over the course of time. But the tannery of the Hulshof family, in the middle of the town of Lichtenvoorde, has proudly withstood the test of time. Hulshof Royal Dutch Tanneries is the current name of the company, whose animal skins are used in car upholstery for expensive Ferraris and in exclusive Gucci bags. Soon, Hulshof hopes to also be known as a producer of high quality, biobased fats and proteins, extracted from subcutaneous tissue, organs and other animal waste material.

Using waste material more efficiently is interesting from an economic perspective, but also has environmental benefits.

‘Extracting fats and proteins from animal waste material is a logical consequence of the development the company is undergoing’, explains Peter Verstrate. Verstrate heads Hulshof Protein Technologies, where waste products are processed into high quality proteins. ‘Using waste material more efficiently is interesting from an economic perspective, but also has environmental benefits. Follow up tests are already being carried out to extract valuable material from skin tissue and fat as well. Hulshof’s leather can be found in products of Spyker, Mercedes, Montis, Gucci and Louis Vuitton. These are companies that expect their suppliers to do everything possible to minimise their impact on the environment.’

Mild and clean method

Hulshof Protein Technologies has been extracting protein from the protein-rich subcutaneous tissue in cattle. The next step is to extract high quality proteins, fats and oils from other animal waste material, such as pig skin, chicken skin and animal organs. This step is being taken through an innovative programme supported by EFRD grants. In doing so, Hulshof uses the DeMythe® technology developed by Akzo Nobel for the leather industry to remove water and fat from animal hides. ‘To extract the remaining fats, we use the gas dimethyl ether (DME) and put it under intense pressure, making it a liquid. The advantage is that it is a much milder and cleaner method than traditional curing methods.’

‘World of opportunity’

Wageningen UR Food & Biobased Research and the NIZO are knowledge partners in this programme. After first identifying which waste material is suited for the extraction of fats and proteins, both research institutes are now analysing the first experiments involving protein and fat extraction taking place in a factory in Barcelona. Meanwhile, Verstrate is about to open a brand new testing facility in Groenlo, the Netherlands. ‘Here we will work on specific applications for fats and proteins that have stimulated interest on the basis of the analyses. Take for instance collagen, a protein used frequently in the cosmetics industry and plastic surgery. In Groenlo we will soon be able to extract this protein from pig skin. We are searching for possibilities of which we do not yet know which are the greatest. A world of opportunity lies before us.’

Fewer animals needed

Verstrate has worked in the meat processing industry his entire life and is pleased about these developments in the biobased economy. ‘We can produce leather because people eat meat. And that meat consumption, as a result of the global increase of wealth, is reaching limits. This is not a moral standpoint, but a fact. A small part of the problem can be resolved by improving the efficiency of the process. This project is an example of this. By using meat waste material more efficiently, we need fewer animals for the same amount of final goods. Together with our knowledge partners we can make a small, but significant contribution to this effort.’

Verstrate is pleased to have Food & Biobased Research as a partner. ‘Wageningen UR has much fundamental knowledge, but it also offers many possibilities for performing analyses and determining which application possibilities there are in the market. For this reason they are not only valuable partners for the development of knowledge, but also for the commercial development of the project.’

‘Enormous potential’

The study into protein and fat extraction from animal waste material started in September 2011 and will run for three years. The participating parties, according to researcher and protein specialist Wim Mulder of Food & Biobased Research, have made clear work agreements. ‘For instance, NIZO will focus their research on possible food applications, while we will investigate opportunities in non-food applications. Think of biocoatings, surfactants or chemical building blocks for bioplastics. There is enormous potential. According to calculations by Hulshof, 10% of cattle protein is located in subcutaneous tissue. If we use that, we will need 10% fewer cattle worldwide for protein production.’

Alternatives to fossil fuels

Fellow researcher Rolf Blaauw is studying the application possibilities of oils and fats. ‘We are currently researching how we should design the DME process to extract raw materials as efficiently as possible. On the basis of their composition, we examine whether they are suited for the production of products such as biobased diesel or lubricants, products which are currently still being made from crude oil. The need for alternatives to fossil fuels is one of the reasons this project is important. A second reason is that it provides a more efficient way of ‘using the animal’. A third reason is that it is very interesting economically for companies: they can extract value from waste material that was previously discarded.’

Verstrate estimates that a global breakthrough might be imminent. ‘Once our factory in Groenlo is running properly, more companies worldwide will start using animal waste material.’

Participants in the project are: Hulshof Protein Technologies, Wageningen UR Food & Biobased Research, NIZO, Akzo Nobel, Noblesse and Smit & Zoon.