Coca-Cola is one of the most iconic brands in the world, known for its famous contoured glass bottles. However, in recent decades, the company has moved away from returnable glass bottles and transitioned to using plastic and aluminum. This shift away from glass has been driven by several factors.
The rise of plastic bottles
One of the biggest reasons Coca-Cola stopped using glass was the rise of plastic polyethylene terephthalate (PET) bottles in the late 1970s. PET bottles were cheaper to produce, lighter to ship, and more shatter-resistant than glass. As they became more widely adopted across the beverage industry, Coca-Cola saw an opportunity to reduce costs and improve convenience by switching from heavy, fragile glass to lightweight plastic.
In 1977, Coca-Cola test marketed the first 2-liter plastic bottle. By 1983, plastic bottles outsold glass, and by 1984, Coca-Cola sold more product in plastic than glass for the first time in history. Plastic bottles were easy to recycle or discard, and their lighter weight dramatically reduced shipping costs compared to glass. Over time, plastic also lent itself better to larger, bulkier sizes like 1-liter and 2-liter bottles.
The challenge of recycling glass
Another factor was the difficulty of recycling glass bottles efficiently. Prior to the 1970s, Coca-Cola relied on a bottling and distribution system that primarily used returnable glass bottles. After delivering full bottles to a store, the empty glass bottles would be taken back, sanitized, refilled, and shipped back out.
While this created less waste, it was an extremely labor and resource-intensive process. Transporting, cleaning, and redistributing millions of empty glass bottles back to bottling plants required significant time, effort and fuel. And the system had high breakage rates, resulting in further waste.
As recycling programs were established in the 1970s and 1980s, glass recycling proved challenging. Glass is heavy and costly to transport, and broken glass can contaminate other recyclables like paper. Recycled glass also has impurities that limit its reusability, whereas PET plastic bottles could be more efficiently recycled into new containers or other products. For these reasons, glass recycling rates remained low compared to lightweight, versatile plastic. Coca-Cola realized it would be more economical to switch from refillable glass to recyclable plastic bottles.
The aluminum can advantage
At the same time plastic bottles were taking over, Coca-Cola began expanding availability in aluminum cans. Although soda cans had been around since the 1960s, improving can manufacturing technology and consumer demand for portability and convenience drove increased usage.
Much like plastic, aluminum cans weighed less than glass and were more durable and resistant to breaking. Cans were quick to chill, portable to take anywhere, and stayed carbonated longer than plastic. Cans also provided excellent protection against light and oxygen to retain flavor.
Additionally, aluminum cans have higher recycling rates than glass bottles. Aluminum can be economically recycled over and over, while glass must be reprocessed with raw materials each time.
Aluminum can recycling rates
| Year | Aluminum Can Recycling Rate |
|---|---|
| 1970 | 16% |
| 1980 | 17.9% |
| 1990 | 62.7% |
| 2000 | 65.1% |
| 2010 | 55.1% |
| 2020 | 53.8% |
As seen in the table above, aluminum can recycling rates surged beginning in the late 1980s, making cans an environmentally and economically smart packaging choice. Coca-Cola ramped up production of canned products to capture this trend.
The risks of glass bottles
As plastic and cans gained prominence, glass bottles became seen as outdated and hazardous. Glass bottles broke easily, both during manufacturing and distribution as well as in consumer use. Breakage resulted in monetary losses as well as safety issues.
Glass shards could injure workers and consumers, expose products to contamination, and require costly cleanups. There were also risks associated with the thickness and weight of glass bottles. Thicker bottles were safer but used more raw materials, drove up costs, and created more waste. Thinner bottles used less glass but broke easily. Compared to plastic and aluminum, glass seemed risky and wasteful.
Changing consumer preferences
Another major factor was shifting consumer preferences away from heavy, reusable glass containers. Throughout the 20th century, consumers gravitated toward single-use packaging and self-serve retailing.
Younger demographics preferred lighter, unbreakable, convenient packaging. Cans and plastic bottles were seen as modern, while glass seemed old-fashioned and cumbersome. With lifestyles becoming faster-paced and households getting smaller, consumers wanted drinks in smaller, ready-to-go containers. This fueled the demand for disposable cans and bottles instead of refillable glass.
The environmental impact debate
The rise of environmental awareness introduced debates about the sustainability of different beverage packaging options. By the 1990s, some environmental groups criticized plastic and CANS as wasteful and harmful to the planet. This led to questions about whether Coca-Cola should revert back to refillable glass bottles.
However, glass bottles have drawbacks too. Producing glass generates greenhouse gas emissions from energy intensive smelting and manufacturing processes. The weight of glass leads to more fossil fuel use during transportation. And while glass can be recycled, it must be reprocessed using raw materials each time.
Ultimately, no packaging is perfect. Plastic, cans, and glass all have environmental trade-offs. Coca-Cola determined that lightweight, recyclable PET and aluminum was the most sustainable and economical choice compared to heavy, breakable glass. But the company continues researching how to improve its packaging footprint.
Changing distribution and retail models
How beverages get delivered, stored and sold has also significantly changed over the decades, moving away from a refillable bottle model.
Initially, Coca-Cola was distributed in glass bottles to pharmacies and soda fountains. But as grocery stores, vending machines, and self-service retail expanded in the 20th century, distribution evolved. Pre-filled, disposable containers in cans and plastic optimized efficiency in self-serve stores. Refilling glass bottles at stores became impractical.
The rise of big box retailers like Walmart and Costco drove adoption of bulk packaging like 2-liter bottles over smaller glass bottles. As consumption shifted to the home, disposable packaging minimized shelf space needed at retail. Cans and plastic bottles fit better with this new retail landscape.
Innovation in glass manufacturing
Despite moving away from glass, Coca-Cola has continued innovating in glass bottle technology. In recent years, the company introduced new glass bottle shapes, lightweighting, and sustainable sourcing:
- Contoured shape – Coca-Cola’s famous bottle shape was designed to be recognizable even when broken.
- Lightweighting – Advances in glass technology allowed Coca-Cola to produce lighter glass bottles that use less material.
- PlantBottleTM – In 2009, Coca-Cola introduced the first fully recyclable PET plastic bottle made using biomaterials. Up to 30% of the bottle’s material comes from plant byproducts.
- 100% recycled plastic – Coca-Cola has committed to making bottles with an average of 50% recycled plastic by 2030.
- Renewable sourcing – Coca-Cola sources glass bottles from suppliers committed to sustainability and recycling.
So while glass bottles have been largely phased out, Coca-Cola still utilizes glass for certain specialty and premium products. The company also continues driving innovation in glass and other packaging.
Conclusion
The shift away from heavy, breakable glass bottles enabled Coca-Cola to cut costs, reduce waste, meet consumer demand, and adapt to modern retail. Lightweight plastic bottles and recyclable aluminum cans became the packaging of choice due to their portability, safety, and recycling efficiency. Although no packaging is perfect, PET and aluminum cans have proven to be the optimal choice balancing environmental impact, safety, affordability, and consumer lifestyles. Coca-Cola’s packaging will continue evolving, but glass has become unsuitable as the primary retail packaging for sodas in today’s world. The next frontier will be developing new sustainable packaging materials to completely phase out traditional plastic.