In the UK one third of food is thrown away. We can assume that this statistic is similar for the rest of the developed world.  Of that food thrown away, 61% is avoidable, 20% is possibly avoidable and 19% is unavoidable.  Food as trash generates methane, which is why we have methane in our landfills.

Examples of avoidable include tossing unused food; possible avoidable might include food that is past its sell-by date. For instance, up to 10% of residual food is left in containers. Is there packaging that would enable getting the last of it out?

Food creation is the number one ecological impact. It is far bigger than the packaging that contains it. Therefore the most important role of packaging is to insure that its contents gets fully used and, second, that the packaging itself is reused or recycled in some fashion.

Packaging reduction that results in any increase in food loss is more environmentally damaging due to the food loss. We need to remember that when we think about packaging reduction.