Don’t beat yourself up the next time you toss some yogurt slightly past its expiration date or the mildly moldy cheese you don’t want to cut around – billions of litres of raw milk used to make those and other dairy products went down the drain long before it left the farm, a new study suggests.

As published in the journal Ecological Economics, the authors’ low-end estimate for milk that “vanished” from Canadian dairy farms between 2012 and 2021 at over 6.8 billion litres. By their accounting, that amount – enough to provide for 11 per cent of Canada’s population – would have had a retail value of $6.7 billion.