Food for thought on emissions

Maria Gunady loves food, so when it came time to start her honours project, focusing on fresh produce was the obvious choice.

Using lifecycle analysis, Maria investigated the emissions generated by the production, packing and transport of cos lettuces, button mushrooms and strawberries.

The idea was to help identify ‘hotspots’ where the highest emissions were generated in order to eventually work on reducing greenhouse emissions.

And it was that research that resulted in the Curtin food science student becoming a finalist in the WA Young Professionals in Agriculture Forum award.

“My supervisor and I started off thinking about doing something with food miles, but food miles aren’t really applicable in the sense that there are a lot of other factors at play,” Maria said.

“The climate change idea came after that. It’s a huge issue.”

Three different products were chosen and questionnaires were developed for farmers to fill out.

“I went to farms and looked at how farmers started from cultivation to harvesting and packing,” Maria said.

“From the information from the questionnaires, we calculated the amount of greenhouse gases emitted from different stages — from cultivation, to harvest, packing, storage and transport. From that, we can see which stage produced the highest greenhouse gas emissions.”

Lettuces were found to have the highest level of emissions, creating 5.18 grams of carbon dioxide equivalent to produce one kilojoule.

But it was identifying how those emissions were produced that was significant.

“With mushrooms, for example, we get the raw materials from overseas and from Melbourne, so transportation of those materials would be the hotspot,” Maria said.

“For lettuces and strawberries, it’s the use of machinery for cultivation.”

Machinery operation contributed to 53 per cent of emissions in lettuces and 58 per cent in strawberries.

The transportation of peat, compost and spawn made up a staggering 81 per cent of emissions for mushrooms.

“We have identified the hotspot, but how to overcome it is probably more difficult,” Maria said.

“For example, we identified if you use a multipurpose tractor then it might reduce the amount of greenhouse gases because of the diesel that the equipment uses. But that means you need to buy a new tractor, which is not cost-effective, considering one tractor could last years.

“It’s probably harder to implement how to overcome those problems but the first step is to identify what the problems are and from that process will come the answer of how to fix it.”

For now, Maria is working at Coles in quality assurance for fresh produce, but she admits she would like to continue with her studies.

“I’m thinking of doing my PhD,” she said. “I love how we can develop a new product to make food more interesting.”