During this Compost Awareness Week, there are four great things that we should be aware of with composting our food waste.
If food waste is well aerated during composting, odour is eliminated within two weeks, and the moisture content reduced from 65% to 50% or below.
Achieving this requires a well designed process and a well designed recipe, allowing air to move freely through composting mixtures that include up to 50% food waste. Its easy to find news stories of odorous composting processes. The key is good management, including compost system design and compost recipe preparation. If we don’t get it right early on by providing enough air, the odour may linger in the compost for a long time, possibly many months.
Encouraging fungal growth is important to kill potential pathogenic bacteria such as E. coli. We like to see temperatures of > 55 C for at least three days in all of the food waste being composted. Controlling moisture, temperature and the oxygen after this initial composting phase is important to encourage fungal growth.
Compost produced from food waste is rich in nutrients, so its more like an organic fertilizer than a “soil”. We can’t use it directly to grow plants in, but is a great product to add to existing soil to provide nutrients and healthy microbes. Food waste compost is an excellent product to improve the health of our soil, and should be returned back to the land in order to grow food or beautify our environment.
Successful composting can be done at home or on a small scale. It is important to contain the process, protect it from rats and other vectors, and ideally insulate it to allow the higher temperatures to be achieved. The composter has be be designed to allow hot moist air to escape and allow cool air to be drawn through the bottom.