Glass bottles for wine… and the environment?

Packaging alternatives to glass bottles have, to date, hardly played any role in the wine industry. Many consumers regard wine in glass bottles, especially in the form of the common 1.0- and 0.75-liter bottles, as a part of wine’s identity.
© / User: Scot Warman

As a material, glass has been used for thousands of years. Its benefits were recognized early on, be it in the form of beverage or storage receptacles or even as glass panes for the first windows installed in Roman villas. Glass is transparent, sturdy and tasteless, and when used as a receptacle can be hermetically sealed. This is why glass bottles are nowadays seen not only as a mark of quality, but they also play a key and much discussed role environmentally.

Contrary to what many people assume, glass is neither a crystal nor a solid but, in fact, a solidified liquid. The liquid cools so rapidly, that its structure corresponds to the liquid state leaving insufficient time for silicate (main constituent of glass) crystals to form.

Industrial production makes glass an everyday object 

We make everyday use of glass in the form of bottles. Industrial production of glass bottles was introduced at the beginning of the 19th century and has been continuously improved by the launch of new methods. The production of glass from a hot molten mass requires a great deal of energy, which is why the ongoing aim is to reduce energy inputs.

Despite intensive research into producing glass with a greater degree of energy efficiency, its future as a packaging material for liquids has seemed to be in decline for a long period. The entire beverage industry has opted to use new materials, whether it be aluminum in the form of cans, carton packaging for juices or easy-to-produce, lightweight PET bottles for mineral water, sweetened beverages and sodas. At 280 grams, a standard half-liter beer bottle made of glass weighs ten times as much as a PET bottle of the same size. This represents a considerable difference as far as transportation is concerned.

Glass bottles – the classic for wine

Packaging alternatives to glass bottles have, to date, hardly played any role in the wine industry. Many consumers regard wine in glass bottles, especially in the form of the common 1.0- and 0.75-liter bottles, as a part of wine’s identity. The only exceptions are carton packaging in Tetra Pak format and bag-in-box packaging, which comes in 1.5-, 3- and 5-liter versions. These consist of carton packaging and a pillow pouch with a dispensing valve. In some countries they are very popular. For example, in Scandinavian countries, bag-in-box packaging accounts for around 50 percent of wine sales. Easily transportable, wine in bag-in-box packaging goes hand in hand with Scandinavians’ leisure activities like camping and boat trips. In Italy, Tetra Pak and other comparable forms of carton packaging are the standard selling unit for simple table and everyday wines.

The situation is very different in Germany. Here, the glass bottle dominates the wine market and consumers regard it as necessary. According to industry estimates, more than two billion glass bottles are sold in the German market annually, the bulk of which are filled in German wineries.

Reusable bottles currently account for less than 20 percent in the wine segment. However, the overall recycling rate for glass is high due to the take-back system organized via the Green Dot (Der Grüne Punkt) scheme where every manufacturer pays fees. According to Düsseldorf-based BV Glas, (of which the twelve glass bottle manufacturers operating in Germany are also members) there are more than 250,000 bottle banks (glass bottle collection points) throughout Germany, which are used by 97 percent of households. Generally speaking, glass is an exemplary material as far as recycling rates are concerned. According to the association, some types of bottles now consist of up to 90 percent “old” fragments. The current average is 60 percent per glass bottle.   

PET vs. glass

The weight advantage of PET and the lower energy consumption involved in the manufacturing of it have an impact on environmental life cycle assessments (LCA). Reusable systems can be set up for both materials (PET and glass), therefore enhancing environmental life cycle assessments considerably. Which LCA is better depends on the circumstances, return rates, transportation distances and producer-to-consumer-to-producer logistics applying to each production facility. Glass bottles, for example, can be refilled 50 times, while the refilling rate for PET bottles is only 20 to 25 cycles.

Etwa 40 Prozent der in Deutschland verkauften Weine stammt aus deutscher Weinproduktion, die anderen 60 Prozent der abgefüllten Weine stammen aus dem Ausland.
© / User: Yoko Correia Nishimiya

In 2016, reusable bottles only accounted for just over 40 percent of the beverage market. Ten years previously, two thirds of all beverages were sold in reusable packaging. This reduced rate caused the legislature to get involved, and has therefore demanded a new target rate of 70 percent in the new German Packaging Act (2019). Bottles on supermarket shelves must now be labeled, indicating whether they are reusable or single-use. 

The debate about issues ranging from consumption of resources and use of raw materials to the littering of the world’s oceans has flared up at a broad societal level. This is more likely to cause consumers to change their thinking than statutory regulations.

Glass is currently undergoing a true renaissance in the beverage industry and all market players are increasingly focusing on it again. Reusable glass bottles are on the rise, especially in the mineral water segment. Reusable glass bottles now account for 13.9 percent of the €13 billion non-alcoholic beverage market, just under the figure for reusable plastic bottles.

Traditional beverage manufacturers are increasingly opting to use glass

As a result of the broad climate change debate, more and more beverage manufacturers are increasingly opting for glass again. In the last few months Coca Cola, numerous mineral water producers, and Austrian energy drink producer Red Bull have all launched new products in glass bottles.

Some 40 percent of the wine sold in Germany is produced by German wineries, while the remaining 60 percent of bottled wines are sourced from abroad.

Likewise, these producers have specifically invested in glass bottling plants. For traditional users, the current demand for glass has had an unwelcome effect, as Peter Mohr, CEO of Wittwer, a Rhineland Palatinate-based glass wholesaler, explains. The increased demand at the beginning of 2019 led to a shortage of glass packaging on the market which in turn also affected German vintners and wineries. For several months, quite a few types of glass (dark green liter bottles for wine, for example) were hard to come by.

The situation was made worse by the temporary outage of several glass melting furnaces at major glassworks in southern and eastern Germany, which had to be repaired. Given the high temperatures at which they operate, glass melting furnaces are subject to constant wear and tear, specifically, the contamination of base materials caused by metals gives rise to major problems.

The situation has now eased somewhat. Glass bottles, be they the traditional liter bottles in green or the 0.75-liter bottles in various shades of green, in white or in brown, are available again.

Glass packaging at drinktec 2021

Glass remains an important and sought-after material that the beverage industry can’t do without. Given that it can theoretically be 100 percent recycled, this makes the material doubly prized in this day and age. Established and new providers, as well as innovative products from all sectors of the beverage industry will be showcased at the Munich technology trade fair, drinktec 2021, which takes place at the exhibition grounds from September 13 to 17, 2021.

Have you developed innovative options for glass packaging that you’d like to present to an international audience? Then join us at the next drinktec.

Dr. Hermann Pilz

Dr. Hermann Pilz has been in charge of the trade magazine WEINWIRTSCHAFT as chief editor for over 20 years. He loves writing about many different topics of the wine and spirits industry.