Pablo Juliano wants to feed the world with innovative processes that waste less food and maximise nutrition and flavour.
The United Nations estimates that 821 million people around the world go hungry every day. The number of people facing undernourishment is projected to rise to more than 2 billion people by 2050.
Yet the world wastes 1.6 billion tons of food each year, rising to an expected 2.1 billion tons by 2030, according to a recent study by Boston Consulting Group.
In Australia, the estimate is $20 billion lost (before retail) or wasted (after) in the 2016-17 financial year, totalling 7.3 million tonnes.
The National Food Waste Strategy (NFWS) aims to halve this volume by 2030. It points out that, currently, a quarter of vegetables grown don’t leave the farm, and Australian households waste enough food to fill “close to 17,000 grounded 747 jumbo jets”.
The numbers are shocking, but optimists say we can do better, and that, as with any challenge, there are opportunities.
Dr Pablo Juliano is one of the optimists. He has spent his professional life thinking about how food engineering can improve the world.
The Group Leader of Food Processing and Supply Chains at CSIRO, Juliano was drawn to the field’s potential, became immersed in the complexity of industrial and research problems, and has returned to questions about what can have the most impact for the most people.
He was CSIRO representative on the NFWS and led the mapping of food and vegetable value chain waste around Australia, published last year.
Problems of food tend to be made of many parts, whether at the supply-chain or processing-line level.
“The challenge of food engineering is that you have a complex material such as food – a multi-component material where the engineering properties of that are quite complex – but also there are aspects of how microbes survive in there and what happens to the components and how do they interact with each other to make it taste good and to be safe,” Juliano told create while describing his PhD thesis on high-pressure, high-temperature (HPHT or HPTP) sterilisation, which he completed in 2006.
Applying pressures up to 700 MPa and temperatures up to 121 degrees Celsius to deactivating microbial spores, Juliano demonstrated the technique as a promising alternative to conventional thermal processing. The work is part of how he ended up at CSIRO.
Industrialising HPHT remains elusive. Juliano’s doctoral work was driven by a military problem – thermally processed egg rations had poor taste and colour – and the results “underpinned the development of a core CSIRO technology,” Juliano said.
“This caught the attention of CSIRO, basically because CSIRO had a similar machine to the one that I was using in the USA and an industry-government-academia consortium was using.”
He has since left this work behind, contributed to the development of some very different technologies, and is now involved in getting them out of the lab to where they can make real change.
Pressure and progress
Juliano was drawn to food engineering by what he calls “the social side of science”.
The discipline had only just started to be offered in 1993 when he entered Uruguay’s Universidad de la República. He saw himself having a role in the country’s dairy and meat industries.
“I thought, well, food engineering is a technical degree that could take me into the food industry, and I could leverage that to improve the wellbeing of the world in some way,” he recalled.
During university he began at Nestlé Uruguay as an analyst, before rising up the ranks to head quality assurance at the company.
Juliano’s master’s study brought him to Washington State University and research on powder behaviour and hopper design, before he turned to the high-pressure sterilisation PhD work that drew CSIRO’s attention.
His Food Science Australia (FSA) – a joint venture between CSIRO and the Australian Food Industry Science Centre – postdoc stint was followed by a year back in Uruguay as head of research and development (R&D) at dairy giant Conaprole, and then a return to Melbourne as CSIRO Principal Research Scientist.
Dr Kai Knoerzer, who is also now Principal Research Scientist, was a postdoc in the 2006 FSA cohort, and has led the engineering development of HPTP. He said HPTP has been identified as the “next disruptive innovation” in his field, particularly for chill-stable and shelf-stable, low-acid food and beverages.
Cold pasteurisation by high-pressure processing (HPP) has been part of CSIRO research and development since 2001, and has been commercialised through a handful of companies, most notably Preshafruit. It uses a batch process that takes from two to five minutes and isostatic pressure up to 600 megapascals to “crush” and inactivate microbes. Because it doesn’t act on covalent bonds it doesn’t change the taste of a substance.
HPTP, on the other hand, combines both pressure and mild heat to enable sterilisation. It uses temperatures of 60 degrees Celsius HPP pressures (or 600 MPa) to make food and drink microbially safe.
This synergy of lower heat at pressure offers potential benefits in fresher tasting products, fewer preservatives, and retention of nutrients. Knoerzer has a patent on a system consisting of a multi-layered polymer canister to “drop in” to HPP machines, thereby allowing HPTP in commercially available machines.
Business planning and commercialisation endeavours are underway, with the first products using this technology entering the market in the near future.
“HPTP will play a big role in new product development and applications such as modulating the texture of food – for example, meat tenderisation of low value meat cuts, toughening of seafood products, etc.,” he told create, adding that a commercial-grade machine would be at least twice as expensive as an HPP system, and maintenance requirements would be enormous.
Juliano’s group is involved in a host of other processing techniques, including fermentation, spray drying, microencapsulation, extrusion and megasonics.
Megasonics uses high-frequency ultrasound to separate oily or fat ingredients. For Juliano, this work began with milk fat fractionation and moved to applications such as separating olive oil and palm oil from slurries. It has earned him recognition including a Julius Career Award (2016-2019) at CSIRO, and a finalist spot in the 2018 Eureka Awards.
The process involves heating palm fruit flesh to 130 degrees Celsius, adding water, and crushing it all. Transducers apply ultrasound waves to the mix before it is put in a clarifier and the oil is skimmed.
“We were able to show that we have much faster oil separation but also oil recoveries of one per cent extra oil. Within a 45 tonne-an-hour process this is a huge advantage,” Juliano explained.
“It started with 7 mL, going to 100 L, going to 5 t an hour to prove the concept. And now we are at 45 t an hour, two companies are using the technology in Malaysia and we have a deal with a commercial partner in Malaysia.”
Waste not, want not
It’s an interesting time for those looking to make the food industry more efficient. If the technical challenges aren’t enough, then the new circular economy throws up myriad issues.
“Individually they’re surmountable but, taken en masse, you end up with a very restricted sort of environment that is no one’s fault,” Dr Paul Luckman, chemical engineer and Fight Food Waste Cooperative Research Centre (FFWCRC) Transform Program Leader, told create.
The FFWCRC was announced in 2018 and is funded until 2028. Among its aims is identifying technological gaps and process limitations to turning waste streams into value-added products.
One project will examine ways to find a home for the vast amounts of biomass lost in the potato industry. Up to 40 per cent of potatoes grown are rejected for reasons such as their appearance, and this material has potential to be used in higher-value applications. A tonne of rejected potatoes might be worth $10 as fodder, but a tonne of potato starch might fetch $500 to $800.
“There are a lot of products used in fermentation which are very valuable, particularly for food additives in terms of enzyme-resistant starches, and all of those aren’t being utilised right now,” Luckman said.
Another approach to waste involves stabilising and drying biomass, combining it with other ingredients, and extruding it.
Dr Danyang Ying is one engineer at CSIRO investigating extrusion, applying it to broccoli, carrot, and pomace. He hopes to make nutritious snacks out of what might otherwise be thrown out.
Ying has worked with extrusion for nearly 20 years and for six years at CSIRO, where he is a Principal Research Scientist.
“Extrusion is a versatile processing technique which combines multiple unit operations, such as mixing, heating, melting, puffing, shaping, into one process,” he told create.
Ying agreed that waste-to-value is an interesting area to be working in at the moment, with a global population tipped to reach nine billion in 2050, limited arable land, and the effects of climate change squeezing resources.
“By turning those edible biomasses into stable food ingredients and transforming into nutritious and attractive products, farmers could have an alternative income from that produce that is not suitable for fresh produce market,” he said.
“These are similar to the physical process that you might find in the minerals industries or in the chemical engineering industries.
“The more engineering work that is invested in developing a food process, that will be achieved in improving processing efficiencies, making food stable, safe and nutritious, improving the logistics, removing the water, recovering the water, and treating the effluent to the point that you can recover a lot of the food that is wasted.
“In a nutshell, all of that says: yes, engineers have a role in improving food security.”
This article originally appeared as “Transforming food tech” in the April 2020 edition of create magazine.
