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Week Seventeen - Food Waste

Save 100 kilograms CO2e per person per year

· Weekly experiments

My preschooler

- My pet worm Slimey sleeps for two days and two nights and then she gets up and dances. She dances like this - and sometimes like this.


- Sounds like a dietary imbalance. Slimey should eat less carrot peel.

Disco worm shows you how it's done

Waste not, want not

Having twice caused mass genocide, I've abandoned worm farming, but I let my preschooler try it. Vermicide runs in the family. Hers died too, no doubt from overfeeding. It highlighted the problem of food waste.


How much food do we waste? Estimates are that from one-third up to 40% of food produced is wasted. Last year in Australia, households and businesses generated 4.3 million tonnes of food waste. 87% of that went to landfill, where it generated per person around 300 kilograms of carbon dioxide and equivalent emissions (CO2e). That only counts the direct emissions from businesses and households. Emissions are much higher once you factor in on-farm waste and the embedded emissions to grow and produce it all in the first place.

Much of this waste is invisible. We don't really know what embedded emissions are in the food we eat, let alone the food we discard. Much is also beyond out control. The industrial food system that gives us restaurants, fast food, caterers and supermarkets generates a lot of waste on our behalf. Think about the salad tossed out after a conference, the sub-grade veggies that don't make it to the shelf or the loaf-ends of bread discarded by a sandwich bar. It's hard to calculate your personal contribution, but it's easy to reduce it.

Dumpster diving

One way to avoid waste from the industrial food system is to dodge that system altogether. I spoke to regular dumpster diver, Imogen, about the local scene. Who's diving in Canberra?

'A lot of divers are anarchists, freegans or students,' Imogen said. ''Also co-ops and those seeking an urban thrill. We often share our food around. You'd be surprised how many people struggle to afford good food.'

Are there any tricks and traps?

'Go at night after the shops shut, so you don't interfere with their operations. Find out what time the supermarkets toss out their food and which ones have the best stuff. Some staff are friendly about diving and others will send you away. Never leave a mess behind or they'll lock the bins and you'll ruin it for everyone. And get in touch with local divers to learn the ropes.'

What was Imogen's best haul?

'I'm vegetarian so I usually avoid meat, but I can never resist prosciutto. Once we got fifteen cartons of eggs. And you usually find forty loaves of bread in every dumpster. The biggest problem with diving is making sure you don't eat too much junk food. A lot of lollies and soft drink get thrown out.'

Imogen is a food expert professionally. She's worked on social justice and environmental food issues in Australia and on international panels. She finds the modern mindset frustrating. 'We've only had our industrial food system for a short time,' Imogen said. 'But no one can see past it. Governments think this is the only way to feed people.'

Dumpster diving in action and the great food you can find

Skip dipped food aplenty. Images courtesy of dumpster diver Imogen & Dumpster Diving Canberra Facebook.

Home-grown / fridge diving

I planned to go dumpster diving for this week's experiment, but Imogen explained that it's a seasonal sport and summer diving is for the strong of stomach. Instead, I cut industrial food waste by harvesting from my backyard veggie patch. I found that by buying less supermarket produce, I harvested more (otherwise, I'm too lazy at dinnertime to stray from the kitchen). I also raided Grandma's fridge for some of excess Christmas ham.

How much CO2e does my food waste generate?

I estimate that from food waste alone, I generate around 640 kilograms of CO2e and the average Australian generates around 770 kilograms CO2e each year. My estimates are more rubbery than usual, so please check my notes for details.

Omitting the direct landfill emissions, it still leaves 348 kilograms CO2e for me and 476 kilograms CO2e for the average Australian (I already counted direct landfill emissions when I looked at household waste in weeks 2 - 4 and I don't want to double-count them).

The figures make me deeply uncomfortable. They're a large and pointless chunk from an overall annual footprint of 22.5 tonnes. If we're going to tackle climate change, we need to tackle this.

How much CO2e did I save?

I estimate that I can easily cut 100 kilograms from my food waste with a bit of urban foraging. I intend to maintain this year-round with some backyard produce, taking party and fridge leftovers that would otherwise go in the bin and following the ten steps below. That means saving nearly 100 kilograms CO2e each year.

Ten steps to reduce food waste

Most families eat out and throw out more than I do, so they should be able to cut 100 kilograms CO2e as well with less extreme measures. If you follow most of steps below you should drastically reduce your food waste emissions, no dumpster diving required.

1) Buy, order and cook less food.

2) Do smaller grocery shops more often, or plan your big shop better.

3) Prepare the right amount of food. Don't over-cater to impress guests.

4) Let kids serve themselves, instead of stacking their plates too full and then tossing it out.

5) Buy irregular produce or food marked down for quick sale to save it from the bin.

6) Store food properly and eat it before its use-by date. You can safely ignore 'best before' dates.

7) If you eat meat, eat the organs as well as the muscle. Personally, I'd rather go vegan, but sweetmeats are a more ecofriendly option.

8) Never waste perishable and carbon-intense items, like meat and cheese. Buy small amounts and eat all of it.

9) Keep inedible food waste out of landfill. Put vegetable peels and teabags in an organics bin or use them in compost, worm farms or chicken feed.

10) Encourage your regular restaurants to reduce waste and to keep any scraps out of landfill.

broken image

'The Far Side' cartoon by Gary Larson

Spreadsheet calculations, reference list and data discussion in the 'Notes' section, Week Seventeen.