Many of us have been tucking into our Christmas dinners, but we rarely take time to think about what happens to the leftovers from producing all the delicious food of the season. However, without wanting to spoil your appetite for the inevitable leftovers, there is an important policy issue for what we do with waste biomass, including meat and bone meal (MBM) and household food waste. Getting the most carbon emissions reduction at best value for money is currently a missed opportunity from this waste stream.