This month, Ray Rowlands, takes a look at the developing role of PET in soft drinks and its environmental impact.

Today, the most common vessels for soft drinks are plastic and glass bottles or metal cans. Glass bottles have been around for centuries; cans and plastic alternatives are somewhat more recent innovations. The tin can was patented in 1809 whilst the modern aluminium beverage can was first used commercially over 50 years ago. Plastic bottles were similarly introduced in the middle of the last century but took a few years to be adopted by soft drinks producers.

The soft drinks bottle, so prevalent today, is made of polyethylene terephthalate (PET), a strong yet lightweight plastic. It started to be used as packaging as recently as the mid-1960s but only became widely used for beverage containers in 1977. Since then, the substitution of PET for glass, metal, and other plastics has been phenomenal. Its popularity has been driven by its well-known attributes; clarity, robustness and versatility. As a beverage container, PET offers consumer convenience, extensive scope for innovation and good potential for brand differentiation.

As far back as 1999, PET was used for almost 50% of global soft drinks volume. Today, that contribution exceeds 60%. Over the same period of time, the share held by glass and metal has shrunk back from around a third to one fifth of the total market. Glass has suffered more than cans. Not only has it shed share but it has also lost actual volume.

PET usage in the soft drinks arena is often closely associated with carbonated soft drinks (CSDs); close to one in six litres of all CSDs are sold in PET containers. Yet, the material’s penetration of the bottled water market is actually far greater. Some eight out of every ten litres of bottled water is sold in PET containers. This is all the more remarkable when considering that water can be packed in a wider assortment of packaging materials (including cartons and pouches) than CSDs.

PET bottles can be used for a single filling occasion or they can be reused. Whilst many countries still employ refillable bottles, the non-refillable alternative is more common because of its overriding convenience. However, even when no longer employed for its original purpose the PET material can be recovered, broken down and converted into new resins. If the PET is unsuitable for further recycling (for example, it is too contaminated), it can be used as an energy source (thermal recycling). When all else fails, the bottles can be crushed and disposed of in landfill. In fact, a controversial study by SRI Consulting in Ireland in 2010 reported that a recycling facility needs to recover at least 50% of the material it takes in if it is to achieve a more environmentally-favourable carbon footprint than simply disposing PET directly to landfill, due to the resource costs involved!

Though popular with soft drink producers and consumers for a myriad of reasons, PET does have its critics, besides competing packaging suppliers. Major opposition comes from environmental groups.

The indestructibility of PET has its drawbacks at the end of the container’s life cycle. Petroleum-based plastics like PET do not decompose the same way as organic material does: PET may take 1,000 years to breakdown and may never fully biodegrade

Fortunately, for the planet, soft drink producers are becoming more environmentally-minded and are actively pursuing packaging strategies specifically aimed at reducing their carbon footprint. Coca-Cola, Danone, Nestlé and PepsiCo are four multinationals active in formulating PET bottles with the addition of plant-based material. Coca-Cola introduced the first ‘PlantBottle’ in 1999, composed of PET and 30% bio material derived from sugar cane. Danone followed Coca-Cola’s lead with the launch of Volvic water in a bottle using 20% plant material in 2010. Nestlé subsequently released its Vittel water in a PET bottle containing 30% plant-based material in 2012.

The ‘PlantBottle’ is a step in the right direction, but not the final solution. According to a report published in the Guardian newspaper, the Coca-Cola plant material only constitutes around 22.5% of the bottle by weight. The petroleum-based compound terephthalic acid is responsible for the remaining 77.5%. Coca-Cola hopes to have a market-ready, plant-based alternative to terephthalic acid by 2015. However, PepsiCo may well beat its rival to the post. In early 2011, it announced that it would begin the pilot production of the world’s first petroleum-free plastic bottle in 2012. Its arrival is awaited with keen interest.

Other suppliers have not been standing idly by, but have taken an alternative route to decreasing their carbon footprint. The weight of the bottle for the Bru water brand from Spadel in Belgium has been reduced by 32% in the last ten years. For sister brand Spa Reine, the weight reduction has been 50% since 1971. (The bottle labels are also printed with vegetable ink on recycled paper). Meanwhile, in early-2011, Danone, already active with its Volvic bio bottle, announced that its 150cl PET Evian bottle would use 11% less plastic.

All these moves underline the strong commitment that soft drink producers are showing in attempting to reduce their carbon footprint and adopt an environmentally-friendly packaging policy.