Wine trash – new uses for old garbage

Not all garbage is garbage, at least in the wine business – because wine garbage can be turned into new products, thanks to recycling and upcycling. Christine Neubecker has the story.

Photo by Gary Chan on Unsplash
Photo by Gary Chan on Unsplash

“Sustainability in the wine industry.” It reads like the title of a seminar paper and yet how often has it been said? Another topic that’s frequently discussed is how many levers wine producers can use to save resources. The choice of equipment. The renunciation of bottles that already weigh over a pound when empty. Or the renunciation of herbicides and the turn towards mechanical soil cultivation, which is also a very popular focus. These are all good and laudable measures. But what about recycling management? More precisely: How can waste products be recycled? 

It turns out there are many more options besides furniture from used barriques or lamps and cases from old wine bottles.

From marc to leather

It is estimated that around 10 million tonnes of marc – what’s left after grapes have been pressed – are produced worldwide each year. These remains usually end up back in the vineyard as fertiliser or, in a few cases, are used to produce grape marc spirit. Thanks to new research and technology, however, the waste product is now becoming the raw material for completely new products. In short: the pomace is upcycled. 

One such use comes from the Milan-based company Vegea, which is working in cooperation with Italian wineries. The company was founded in 2016 and has been researching and producing textiles based on organic by-products – in this case, the skins, seeds and stems of the grape. A polymeric compound is extracted from the marc and then coated onto a backing textile, to created sheets of “wine leather”, which looks and behaves much like animal leather. The material is not only vegan, but is also made without solvents, heavy metals and without water consumption, in contrast to the processing of animal leather. The advantages speak for themselves, and so fashion giant H&M has already entered into a collaboration for their Conscious Exclusive Collection Spring/Summer 2020.

Cabernet Sauvignon against ailing roads 

Chilean engineers have discovered a completely different field of application for grape skins. Together with his team, Guillermo Thenoux, Professor of Engineering and Construction Management at the Pontificia Universidad Católica in Santiago, has investigated the effect of marc on the ageing of asphalt roads. The problem is that asphalt roads undergo a process of oxidation over time, becoming stiffer and prone to cracking. “Hence the idea of paving (with) dehydrated and powdered grape marc, as it is a product with a high antioxidant capacity,” explained Professor Thenoux. The result: an addition of the grape marc antioxidant reduced the fatigue and cracking of asphalt pavements by 14 percent. The team used the marc of different grape varieties for its research and discovered the remains of Cabernet Sauvignon performed particularly well, likely due to the higher content of polyphenols in the grapes. 

The core of the matter

When autumn comes and the marc is again distributed in large quantities over the vineyards, there will be oil mill operators clenching their fists, as they see their raw material scattered among the vines. Garpe marc is valuable – to produce one litre of  grape seed oil, for example, the Brian oil mill near Heilbronn in Germany needs 50 kg of kernels. According to the mill, this in turn requires 500 kilograms of pomace, which is then processed to sift out the high-quality kernels. The kernels can then be cold pressed to produce the “green gold”, which is said to have positive properties. Grape seeds are rich in the antioxidant OPC (oligomeric proanthocyanidin), a molecule that shows that may have anti-inflammatory properties – which means it’s a shame to leave it to rot in the vineyards.  Even the by-product of oil extraction – the so-called “press cake” – can be processed into grape seed flour and then used in the kitchen in sauces or breadcrumbs. Silvia Heinrich, who owns a winery of the same name in Burgenland, Austria, works with her daughters to manually sort the grape seeds from the pomace and combine them with thyme and rosemary, to be sold in spice mills.

A lot of wood

Many nationalities like to fire up the barbecue in summer, but in Germany it’s a national obsession. Germans use an estimated 250,000 tons of imported charcoal each year – an amount that’s way beyond their counterparts elsewhere in Europe. Yet when German consumer organisation Stiftung Warentest took a look at what was in the charcoal bags, they discovered that many contained illegally felled tropical wood; five out of the 17 bags tested. 

Yet there is a much more sustainable and obvious solution close to hand, thanks to Germany’s wine industry. Not only do winegrowers use dried vines to light their own barbecues, some will sell portioned bags at the winery or online. for private barbecue enjoyment, but portioned bags can also be purchased on site or online from, for example, the company RebenGlut. 

Pruning remnants normally serve as fertiliser in the vineyard and contributes enormously to the formation of humus. However, some wineries, such as Manincor in Italy or Kollwentz in Austria, to name but a few examples, also use the pruning remnants to produce wood chips for the heating system.

Recycling the closures

Recycling and upcycling play an important role beyond the vinification process. Take the cork, which most people probably think of as the environmentally friendly option. But what happens to it once it’s popped out of the bottle neck?

It doesn’t need to go in the bin, as good cork can be recycled. As an environmentally friendly option, most people probably think of the good old cork. But what happens to it once it has popped out of the bottle neck? Well, it doesn’t need to go into the bin, because good cork can still be recycled. 

The Nature and Biodiversity Conservation Union (NABU) is one of the biggest environmental groups in Germany. If Hamburg office has launched a COR campaign, putting collection points across Germany. The corks are then used to make granulate for insulation.  Sales from the insulation material support crane protection projects in Germany and Spain – it’s cork for cranes, so to speak.

Alternative closures have also been developed around the topic of recycling, such as the project done by Vinventions. It collects and processes both sugar cane-based closures and synthetic corks, to create a new closure from the resulting material. 

This year, Vinventions and its partner company Beologic have used some of the recycled material to create mask bands. Old wine closures have thus become solutions to new problems.

Christine Neubecker

A version of this article first appeared in Weinwelt, Issue 5 2020, published by Meininger Verlag.




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