‘We were shocked’: How Abel & Cole turned to plastic to produce the most eco-friendly milk bottle

Plastic waste has long been a concern for British adults. But while more shoppers placed the responsibility for single-use plastic reduction on manufacturers, retailers and the government according to a 2019 YouGov research, consumers have since adopted more balanced views​. Still, 3 in 10 Britons back a total ban on single-use plastics, while 15% think increased recycling is the best way to reduce plastic waste.  

But an outright ban is easier said than done, and when it comes to food packaging, the picture is even murkier. In the business of dairy, major supermarkets such as Waitrose and Morrisons trialed the use of plastic bags instead of single-use milk bottles, only to find the format did not appeal to shoppers.

More often, manufacturers have aimed to improve packaging recyclability, either by opting for packaging made with higher levels of renewable or recyclable materials, or making changes to popular formats that would ensure single-use plastics can be easily recycled.

And while most milk is sold in retail, 3% is delivered direct to customers through door-to-door deliveries, according to Dairy UK estimates. Yet, this narrow market share hasn’t deterred one of those DTC players to innovate in order to improve their milk packaging’s sustainability credentials.

More eco-friendly than glass

Last November, doorstop grocery delivery service Abel & Cole announced it had chosen plastic to create a refillable milk bottle as the company launched its Club Zero Refillable milk scheme. Far from a backward move, the material of choice came as something of a revelation to Hugo Lynch, Abel & Cole’s sustainability lead.

“When we started a project looking at how we could reduce single use plastic consumption in our milk deliveries, we were committed to find the most sustainable, scalable solution,” he opened. “We wanted to reduce waste but our decision-making also had to be centred on a real term's reduction in the carbon impact of the product.”

In their initial research, the team modeled the use of glass, aseptic carton, high-density polyethylene (HDPE) - typically used for single-use milk bottles - and polypropylene (PP), a denser mono plastic. The aseptic carton had lower emissions than single-use HDPE, but it couldn’t be reused and was difficult to recycle. Glass, however, performed the worst.

“We were shocked by the results we got from life cycle assessment when looking at transitioning back to a traditional glass milk round,” Lynch explained. “Because of the increased packaging weight, it would take glass over 4 uses for emissions to be as low as a single-use HDPE bottle, and 16 uses to reduce emissions to 50%.”

Using glass presented other challenges, too. “Glass can be unreliable choice due to its fragility,” Lynch added. “When handling glass, under health and safety guidance commonly followed by businesses, if there is one breakage in a crate, all bottles in that crate are destroyed to prevent injuries during the sorting process. For our business, this meant unacceptable wastage.”

As for the PP bottle, “we found that we could reach 50% emissions reduction significantly faster - after 5 uses - because the lower bottle weight resulted in less emissions to produce, transport and recycle it at end of life,” Lynch said.

The team now faced a ‘difficult question’: what if plastic wasn’t always the enemy?

Roll-out

And so, after three years of trial and error, Abel & Cole launched a UK-first packaging innovation: refillable plastic milk bottles.

“We designed a 100% polypropylene bottle (PP) that would fit the existing filling infrastructure and supply chain without the need to make costly changes to machinery or posing any health and safety risks, and can be recycled when it reaches its end of life,” he told us. “We were able to access high quality raw material and rigorous chemical tests were completed to ensure that the bottles were ready to be refilled and reused.

“We reverse-engineered the bottle caps and footprint so that we could guarantee it could be washed easily and effectively without any changes to the production process. This meant we could keep costs down and roll the new scheme out to all customers without any price increases so long as we retained a 75% return rate, which we’ve been able to achieve over the 6 months since launch.”

Lynch told is that PP’s low porosity and higher melting temperature allowed for more reliable cleaning, and there is no risk of leeching harmful chemicals into the milk, something that’s been verified by extensive migration and challenge-testing.

Each milk bottle also comes with an ‘early warning’ system to show if a bottle is nearing its end-of-life. “Trials confirmed that labeled bottles could be reused up to 16 times before the label showed signs of degradation,” he added. “This helps us to track bottle life and to ‘retire’ each bottle when it reaches this point, when it is then recycled.”

A positive response

As for how customers and subscribers have responded to the new milk bottle, most of it has been ‘very positive’ – with some shoppers switching to the more sustainable format, boosting the firm's 1L milk sales volumes.

“We have had a very positive response to the scheme,” Lynch said. “As it mimics the previous single-use consumption pattern – customers just have to ‘recycle’ their bottles into our delivery boxes instead of the bin - Club Zero Refillable Milk has seen a 20% uplift in sales week-on-week, in comparison to the single-use 1L bottle.”

“We have tracked an increase in volume of 1L bottles sold, suggesting a proportion of 2L-format customers switching over to 2 x 1L bottles in an effort to buy a more sustainable format, despite this costing them about 13% more.”

The company estimates that 8% of 2L customers had switched to the 1L bottle format, which comprises 42% of the 20% sales uplift. 1 in 4 customers now opt for Club Zero refills, too.

“We have had some understandable concerns expressed by users about the health impact of plastic versus the alternatives,” Lynch added, “and we have been quick to reassure them that our bottles have been tested to the highest standard to ensure they are suitable for multiple uses and washes by the FSA.”

So what’s been the reuse rate since the scheme launched last November? “So far, we’ve been able to reuse 336,000 milk bottles instead of simply sending single use bottles to recycling where the plastic is usually downcycled into a lower grade material,” Lynch told us. “Using our carbon calculator, we have seen that Club Zero Refillable Milk has already saved 10T of CO2.

“We’ve seen engagement growing week on week, with a 20% increase in sales for the 1L format and a return rate now comfortably sitting at our forecast 75% - even reaching 96% in one week.

“We are always keen to improve, and we will continue to focus on increasing the return rate. Given the success of the Club Zero Refillable Milk, we will continue to collaborate with Berkley Farm Dairy to create further refillable NPD that utilises this innovative reusable bottle packaging format, for example, expanding into 2L and 500ml refills.”

Industry interest

According to Abel & Cole, the dairy industry could save 300,00 tonnes of carbon if most of the fresh milk distribution switched to refillable bottles – but what’s the scope to achieving this in reality, we asked.

“There is certainly growing interest in this initiative from the industry,” Lynch said. “There are a lot of challenges to roll this out in storefront retail, but finding ways to retrofit the existing supply chain is something we can all get behind – our hope is that we will see standardisation through the industry, and this will make it easier for all brands to get on board.

“At launch, we estimated that 11,000 Club Zero milk bottles would be sold per week, saving 450,000 single-use plastic milk bottles (23 tonnes of plastic) and 60 tonnes of carbon each year, in comparison to using a glass bottle equivalent. This calculation has been based on a reuse rate of 4; however the bottles can be reused up to 16 times."

"Putting that into perspective, if most of the 7 billion litres of milk distributed in the UK each year switched to reusable plastic, the dairy industry would save a huge 300,000 tonnes of carbon.”