Five meals a week: Scientists audit garbage to assess household food waste

Average weekly waste represented enough calories to feed an adult five nights a week

In this Aug. 29, 2018, photo, at the Waste Management facility in North Brooklyn, tons of leftover food sits piled up before being processed into “bio-slurry,” in New York. A team of scientists spent weeks combing through the garbage of dozens of households to come up with what they say is the most accurate measure yet of how much food is wasted in Canadian kitchens. (THE CANADIAN PRESS/AP/Stephen Groves)

In this Aug. 29, 2018, photo, at the Waste Management facility in North Brooklyn, tons of leftover food sits piled up before being processed into “bio-slurry,” in New York. A team of scientists spent weeks combing through the garbage of dozens of households to come up with what they say is the most accurate measure yet of how much food is wasted in Canadian kitchens. (THE CANADIAN PRESS/AP/Stephen Groves)

Scientists spent weeks up to their elbows in coffee grounds and banana peels to come up with what they say is the most accurate measure yet of how much food is wasted in Canadian kitchens.

“To be honest, it’s not something you’d want to do forever,” said Michael von Massow, a food economist at the University of Guelph.

Food waste has become an increasingly hot research topic in recent years.

Previous efforts have relied on industry data or household self-reporting to assess how much uneaten food goes in the garbage. But people underestimate how much they chuck and industry figures provide little detail on individual homes.

The only way, von Massow thought, was to get down and dirty.

He and his research colleagues worked with 94 households in Guelph, Ont.. The scientists took out the trash, went through recycling, organic waste and composting, separated mushy asparagus from dubious rice and weighed it all out over the course of several weeks.

“Rubber gloves,” von Massow laughs. “It’s not as bad as you might think.”

Items commonly dumped down the sink, such as expired milk or mouldy yogurt, weren’t measured.

The detailed, teabag-by-applecore approach allowed von Massow to precisely measure just how much was thrown out and whether it was once edible. That was crucial for determining the value of what got tossed.

“If you have a T-bone steak and you throw that bone out, putting a value on that bone of whatever you paid for the steak seems inaccurate,” von Massow said.

READ MORE: Save-On-Foods commits to reducing food waste

Waste from the families, all of whom had young children, varied widely. Some threw out up to eight kilograms of once-edible food a week, some barely one-sixteenth of that. The median figure was 2 1/2 kilograms.

That represents enough calories to have an adult over for dinner five nights a week without adding a dime to the grocery bill.

The value of that food was about $18. Producing and disposing of it generated about 23 kilograms of greenhouse gases.

Bread, tomatoes and apples were the top three items. Chicken was the most frequent meat.

Von Massow’s figures are lower than those arrived at in some previous research. A 2017 study estimated the amount of avoidable food waste in Canada at 2.7 kilograms per household.

Von Massow attributes that to his exclusion of non-edible waste.

Going through the garbage was revealing, he said. People know the plastic wrap around that yucky cucumber should go in the recycling, but they toss it in the trash anyway.

“People hide things that they feel guilty about. I saw people hide batteries in a Pringles tube. They know they’re doing something they shouldn’t and I think the same thing happens with avoidable food waste.”

Von Massow acknowledges that his sample size is small and, to some extent, self-selecting. But he maintains his results are, if not statistically bulletproof, at least representative.

The point of the research, he said, is to eventually understand what works best to persuade people to cut down on food waste. For some, it’s an ethical issue. For others, it’s economic and for still others it’s an environmental problem.

For von Massow, spending weeks picking through garbage has already had one effect.

“We have not audited my house yet, but it sure makes me more cognizant of when I’m putting something into the garbage.”

Bob Weber, The Canadian Press

READ MORE: KAPS hopes to get hands on handhelds under Save-On program

Like us on Facebook and follow us on Twitter

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Alberta’s chief medical officer of health, Dr. Deena Hinshaw, announced the province surpasses one million COVID-19 tests Friday. (Photo by Chris Schwarz/Government of Alberta)
COVID-19: Central zone active cases up by 100 in last 24 hours

Most central Alberta communities under province’s enhanced measures list

Sylvan Lake RCMP, Fire Department and Victim Services will be out on Dec. 5 for the annual Charity Check-stop. File Photo
Give Sylvan Lake RCMP the bird at Charity Check-stop

Sylvan Lake RCMP will be accepting frozen turkeys for the food bank during the charity check-stop

Ecole H.J. Cody School. File Photo
Sylvan Lake high school temporarily moves to online classes

Over the weekend, H.J. Cody reported six positive cases of COVID-19

.
Alberta confirmed more than 1,500 COVID-19 cases Sunday

Central zone active cases slightly up

Kyle Charles poses for a photo in Edmonton on Friday, Nov. 20, 2020. Marvel Entertainment, the biggest comic book publisher in the world, hired the 34-year-old First Nations illustrator as one of the artists involved in Marvel Voice: Indigenous Voices #1 in August. THE CANADIAN PRESS/Jason Franson
VIDEO: Indigenous illustrator of new Marvel comic hopes Aboriginal women feel inspired

Kyle Charles says Indigenous women around the world have reached out

Russ and Luanne Carl are sharing about their experiences of fighting COVID-19 this past summer.
photo submitted
Stettler couple opens up about COVID-19 battle

Luanne and Russ Carl urge others to bolster personal safety measures amidst ongoing pandemic

This 2019 photo provided by The ALS Association shows Pat Quinn. Quinn, a co-founder of the viral ice bucket challenge, died Sunday, Nov. 22, 2020, at the age of 37. (Scott Kauffman/The ALS Association via AP)
Co-founder of viral ALS Ice Bucket Challenge dies at 37

Pat Quinn was diagnosed with Lou Gehrig’s disease, also known as amyotrophic lateral sclerosis, in 2013

Minister of Justice and Attorney General of Canada David Lametti speaks with the media following party caucus in Ottawa, Tuesday, January 28, 2020. THE CANADIAN PRESS/Adrian Wyld
Exclusion of mental health as grounds for assisted death is likely temporary: Lametti

Senators also suggested the exclusion renders the bill unconstitutional

Claudio Mastronardi, Toronto branch manager at Carmichael Engineering, is photographed at the company’s offices in Mississauga, Ont., Thursday, Nov. 19, 2020. As indoor air quality becomes a major concern in places of business, HVAC companies are struggling to keep up with demand for high quality filtration systems. THE CANADIAN PRESS/Chris Young
Business is booming for HVAC companies as commercial buildings see pandemic upgrades

‘The demand right now is very high. People are putting their health and safety ahead of cost’

Prime Minister Justin Trudeau speak to the media about the COVID-19 virus outside Rideau Cottage in Ottawa, Friday, Nov. 20, 2020. THE CANADIAN PRESS/Adrian Wyld
Long-awaited federal rent subsidy program for businesses hurt by COVID-19 opens today

The new program will cover up to 65 per cent of rent or commercial mortgage interest

Traffic crosses over the Lions Gate Bridge from North Vancouver into Vancouver on July 2, 2015. Motorists would have to pay a fee to drive into downtown Vancouver under the city's plan to slow climate change but one expert warns it could pose financial hardship for some. THE CANADIAN PRESS/Darryl Dyck
Vancouver’s climate plan ‘first 10 steps in a journey of 10,000,’ says expert

Almost 40 per cent of Vancouver’s carbon pollution comes from vehicles

Alberta has 1,910 active cases of COVID-19 as of Wednesday. Red Deer is reporting five active cases, with 108 recovered. (File photo)
After COVID-related transplant delays, 16-year-old N.S. girl gets lung transplant

‘This is the difficult time now of seeing Tahlia in ICU hooked up to 15 IVs and sedated’

Most Read