BBC analysis reveals a sharp increase in demand for milk in glass bottles since the start of 2018.

As the backlash against single-use plastic grows, campaigns have launched to stop plastic straws and water bottles. People are making changes to their own behaviour every day, reducing their impact on the environment.

Creamline Dairies in Manchester reported that they have signed up more than 1,000 new glass bottle customers, with many switching from plastic to glass.

But waste charity Wrap claimed that the environmental benefit of glass bottles isn’t always clear.

“For glass to be the better environmental option from a carbon perspective, our research shows that any bottle needs to be reused at least 20 times,” a spokesperson explained.

“Less than that and the lifecycle carbon footprint would be greater than for plastic. In practice, glass bottles survive being reused around 18 times.”

It takes energy to manufacture glass bottles and to wash the bottles after each use.

HDPE is a popular plastic packaging choice for milk and other fresh juices. In the UK, four billion HDPE milk bottles are made each year.

It is widely recycled as well. HDPE is 100% recyclable so that it can be used over and over again.

Recoup figures show that HDPE bottles are recycled about 79% of the time in the UK. They are also 15% lighter than they were three years ago.

If you want to take a hands on approach to recycling, you can quite easily turn your old HDPE milk bottles into useful plastic products including plastic bowls, sink plugs, pulleys and plastic welding rod stock.

In fact, if there are any plastic components around your home that need replacing, the chances are you will be able to make it out of HDPE, providing you have the right tools.

Recycling your own milk bottles

  • Check that your milk bottle, or other bit of plastic is HDPE. Most plastics will have a small engraving on the bottom that should tell you what type of plastic it is. Do not mix different plastic together.
  • Wash the plastic milk bottle thoroughly with soap and water and chop it up - first in half, then into strips, and finally into small 1cm flakes.
  • Create a mould. This will depend a lot on what you want to create. If you want to make a plastic bowl then a metal bowl will work well. If you want to later fashion a component, then think about the broad shape that you want it to be. A cylindrical tube will be a good mould for many products.  
  • Fill your mould with plastic flakes and put it in the oven at 180°C, adding more flakes and squashing the plastic down at regular intervals.
  • HDPE will not flow when it is melted, so it’s important that you apply significant pressure as it cools down.
  • Once compressed and cooled, the plastic should be in a useful state. You may want to shape it with plastic shaping tools like a lathe. For some inspiration, watch the videos below.