What is vegetable leather? Under this name that almost sounds like a contradiction, all sorts of materials are hidden.
We sometimes read on the label of a leather goods item “vegetable leather”. However, by definition, leather is a tanned and dyed animal skin. Whether out of concern for the animal condition or environmental concerns, leather, this beautiful material, poses a real problem. On the one hand, breeding consumes enormous quantities of water, is responsible for 6% of greenhouse gas production and can cause deforestation. On the other hand, tanning, most often carried out with chrome, is a major consumer of water and emits toxic waste. Hence the search for alternatives that bring together different materials and techniques, less polluting and cleaner for the planet .
The difference between classic tanning and vegetable tanning
Alongside classic, mineral and toxic tanning, there is vegetable tanning. And it is this vegetable tanning which, recently, justified the mention "vegetable leather" on products.
Classically tanned leather
Tanning is the step that consists of transforming a highly hydrated (and therefore putrescible) hide into leather by chemical treatment, i.e. into a rot-proof, resistant and slightly hydrated material. In more than 80% of tanneries, especially those located in India or Bangladesh, this tanning process uses chromium sulfates. More rarely, aluminum salts (5% of production) or zirconium salts are used. They allow for rapid (24 hours) and inexpensive tanning, to the detriment of workers and the environment. Fortunately, some tanneries now apply strict regulations on working conditions (protection, ventilation of rooms, storage of chemicals, etc.) and environmental impact (wastewater treatment or closed-circuit operation).
Vegetable tanned leather
The leather remains of animal origin, but the tanning is done with plant extracts:
- Chestnut wood, quebracho, oak, catechu,
- Bark of oak, mimosa, pine, spruce, willow, birch or mangrove
- Heather roots, canaigre
- Sumac leaves, gambier
Vegetable tanned leather lasts from 10 days to 8 weeks, depending on treatment.
Although it is incomparably less polluting than mineral tanning, its consequences on the environment are not negligible: chemical modifications and industrial treatments (cutting down trees, treatments for extracting tannins, etc.) persist.
Eco-leather
Richard Wool, an American professor and engineer, invented an eco-leather based on the combination, under high pressure, of natural materials such as cotton (or linen) with corn (or soy) and vegetable oils. He received numerous awards for this promising invention, including the World Green Design Award, the Grand Prix des innovations écologiques, in 2014.
This material would have characteristics very similar to those of leather: water resistance, air permeability and robustness. It would be cheaper to produce and biodegradable. Major sports brands were interested in the concept, but it seems that the professor's death in 2015 slowed its growth.
Vegan leathers, under development
These are 100% plant-based leathers, with the added bonus of having almost no environmental impact.
Pinatex or pineapple leather
Invented by the Spanish Carmen Hijosa after 7 years of development, this vegetable leather is made from pineapple leaves. This by-product of fruit harvests is biodegradable with minimal environmental impact. The fibers of the harvested leaves give, after mixing, a resistant and flexible material, comparable to leather and which can benefit from a finish to give it a particular texture (grained for example).
Eucalyptus leather
Created by the German Fabian Stadler, this very resistant material after transformation of the fibers from eucalyptus leaves, is produced in Germany without pesticides and in short circuits only, for a line of belts under the Noanifashion brand.
Mushroom leather
"Muskin" (a word derived from mushroom and skin) is obtained from mushroom heads, without chemical tanning. We owe this invention to an Italian company: Grado Zero Innovation. Both biodegradable and ecological, this mushroom leather resembles suede leather. Breathable and naturally water-repellent, this organic material also prevents the development of bacteria.
Fruitleather or anti-food waste leather
After realizing that Rotterdam market traders throw away about 3.5 tons of spoiled fruit every day, a group of students from the city created “fruit leather”. During their experiments, the young designers noticed that combining different fruits gives different textures, colors and properties and that Fruitleather can be used in leather goods, furniture and decoration. This new vegan leather is very durable and does not expire. It is odorless and does not attract insects.
Vegea or grape leather
Born in Italy, it is one of the latest and most promising vegan leathers. The Milanese company Vegea has patented this process to transform grape marc, i.e. all the solid and dry materials (skin, stems, seeds) that remain after pressing or crushing the grapes. With some 7 billion tons of this waste from wine each year, grape leather has a future. In fact, it has already won the Global Change Award from the H&M Foundation and the 2017 PETA Fashion Awards Innovation Award. It has even won over the Bentley brand to cover the interior of its cars.
Apple leather
Alberto Volcan, an engineer from Tyrol, has created a leather made from apple juice and compote. Supported at the beginning by the Province of Bolzano, in northern Italy, for the development of his first prototypes of Cartamela (apple paper), he joined forces four years later with the start-up Frumat, specializing in waste recycling. The first applications of apple waste recycling range from kraft paper, tissues, toilet paper, to a wide range of leathers of multiple thicknesses and finishes. Frumat was awarded the Technology and Innovation prize at Green Fashion Carpets in Milan in 2018.
In a leather goods market that has been growing steadily for several years, eco-responsible alternatives to leather are multiplying and attracting new players such as the big names in luxury , sports equipment and home equipment. These fibers have a double advantage: optimization of the resources of the agri-food industry and the ability to adapt to any leather goods product.
