According to a report published earlier this month by WRAP – the Waste Resources Action Programme, UK citizens throw away 6.7 million tonnes of food every year. This is roughly a third of the food we buy. Whilst some of this has to be thrown away, the vast majority of kitchen waste and leftovers can be composted or recycled, rather than just being chucked into the kitchen bin, where it will end up as landfill.
As far as composting is concerned, wormeries are great for processing kitchen waste and are particularly suitable for people who do not have space for a full scale compost heap. However, I found I was producing more kitchen scraps than the wormery could process, which meant that the worms were often overwhelmed.
Bokashi is a great system for processing organic kitchen waste before it is added to a wormery or compost heap. It uses effective micro-organisms (EMs for short) to speed up the composting process whilst eliminating odours and suppressing pathogens.
In commercial bokashi systems, a mixture of bran and molasses are used as a carrier for the micro-organisms. You add kitchen waste to a special bin (ideally with an air-tight lid, as this is an anaerobic process) and sprinkle bran over the top as you go, so that each layer of waste is covered.
When the bin is full, you put it aside for a fortnight, to allow the EMs to do their work. When the fortnight is up, the waste will not suddenly look like compost. In fact it won’t look much different to how it looked before you put it aside. The real difference can be seen when you add the bokashi’d waste to a compost heap or wormery. It turns into lovely, dark, nutritious compost very quickly.
Because of the two week delay between filling your bin and adding it to a composting system, it is advisable to start off with two bins, so that you can start filling the second as the first is put aside.
It is possible to purchase plastic bokashi bins which themselves have been impregnated with EMs. This is said to speed up the process even more. In addition, the ‘official’ bins have a tap for harvesting the nutritious plant food which the bokashi process produces. However if you are just starting out with bokashi, buying two bins and a big bag of bran can be expensive. I bought a couple of small bins from IKEA (of all places) which cost a couple of quid each. They do not have tight fitting lids, nor are they impregnated with EMs, but they work, so I am not convinced it is essential to buy special bokashi bins.
I have found bokashi to be an excellent method of processing my kitchen waste. I have a small bin next to the main one in the kitchen, into which go all the leftovers, peelings etc… In terms of odour, the bins smell a bit pickly if you open the lid, but I don’t find it unpleasant.
Once added to the wormery, the bokashi’d kitchen waste breaks down in a week or so, even despite the fact that I’m convinced all my worms are dead. I’ve already got some fantastic compost from it. My main kitchen bin is considerably emptier as a result.
EMs can deal with cooked and uncooked meat, fish, and even less solid waste such as a few unwanted baked beans. I am now adding much more to the wormery than I was when I just had a box to put peelings into in the kitchen. Absolutely everything goes in there, including onion skins and citrus peel, and it has all broken down nicely. I highly recommend it.
If you buy some cheap bins from somewhere, you only have to pay for the bran. You can get a 1Kg bag for a fiver, which is enough for a few months waste. This is not going to save you money, but at least it is reducing the amount of food going to landfill, and means you don’t have all kinds of smelly food sitting in your bin until bin day.