Researcher recycles stale bread into new loaves

Dr Aydin Berenjian wants to be the world's leading bread recycler. 

In New Zealand alone, 7000 tonnes of white bread is thrown into the landfill every year. That's 10 million loaves.

And it's not just a problem for Kiwis - 1.2m tonnes of bread is wasted worldwide every year.

The University of Waikato lecturer is taking the wasted bread and baking it into new loaves.

The idea started in 2015 as a mutual collaboration between Berenjian and food company Goodman Fielder.

They are the only ones in the world working on reutilising unsold bread.

"Not many people know this but bread which can no longer be sold in supermarkets is returned back to its manufacturer, so the company ends up with lots of bread that is not sold," Berenjian said.

"Usually they make bread crumbs, but the majority ends up in the landfill. And when it goes to the landfill, it causes huge environmental problems, as well as millions of dollars lost."

Berenjian and Goodman Fielder have cooked up a solution using a fermentation process.

"Basically, we get this bread from the company which is no longer sold at the supermarket, put it through a treatment and fermentation process, and the end result is fermented bread.

"Rather than wasting it, which causes lots of financial and environmental problems, we can reutilise it to make it a new, better product.

"When it goes to the landfill, it generates leachate, which contaminates groundwater and also produces carbon dioxide, which contributes to global warming.

"We can reutilise it and take it back to the factory and sell it."

The whole process takes about a day, Berenjian said.

"From getting the bread to doing the different steps to baking and finally packaging – we'd be working from 8am to 5pm to get one tonne of fermented bread."

Feedback Berenjian has received describes the bread as tasting "very good" and somewhere in between white bread and sourdough, he said.

The fermented bread has superior properties to regular bread, Berenjian said.

"It has a high profile of essential amino acids, high resistance starch and a higher shelf life.

"Our bodies cannot produce essential amino acids, so we need to get them from our diet, and the resistance starch is the only type of starch that doesn't digest, so it has huge health benefits.

"The microbes we work with for the fermentation system are all probiotics, so we should expect the health benefits of the probiotics, too, which is mainly improving the digestive system and immunity."

Generally the shelf life of bread at room temperature is three days, but this process enables bread to last seven days,  Berenjian said.

The process he uses kills everything, so in terms of consumption, the bread is completely safe.

There is also a manual inspection stage, because if the bread is too far gone before it gets to Berenjian, it could affect the taste and texture of the bread.

A little mold is okay, but the whole loaf can't be contaminated, he said.

All types of bread can be used, but at this stage Berenjian is working with Goodman Fielder white bread.

"The only difference would be in the taste, but for now we are only using white bread, as it is a major issue in landfills."

As for how many times the bread can be recycled, Berenjian isn't sure.

Berenjian hopes to see the bread being sold within a couple of years.

"If it becomes promising, I'm sure lots of companies will be interested to use this process because 1.2 million tonnes of wasted bread is a worldwide figure.

"It's not just for New Zealand or for one specific company – the challenge is worldwide."