Day 39. Sugar, tomatoes and bees.

We live very close to the British Sugar factory at Wissington and piles of sugar beet are a common sight for us through the Autumn and early Winter.

It's the largest sugar factory in the world, producing over 400,000 tonnes of sugar a year, fairly standard stuff for any sugar factory (after all the clue's in the name). However, at British Sugar they have an integrated manufacturing system which means that the output of one process - waste carbon dioxide streams from processing the beet - becomes the input for another - used by tomatoes during photosynthesis. Who knew? Approximately 250,000 plants are grown each year in the UK's largest tomato glasshouse and more than 8,500 bumblebees, in 170 bee hives, pollinate the crops.

So next time you bake a cake or sweeten your tea, remember the tomatoes (and of course the bees); all part of the sugar production cycle and an output most people won't even be aware of.