August 26, 2024
Food processing is all about change. It takes precision and creativity to turn a specific recipe into something special.
"The first thing that comes to mind when I think of processing is change. We’re trying to change the product in some way to meet a specific need or desire at the time of consumption,” says Helena Arph.
Helena is a food technology specialist at Tetra Pak, where she and her colleagues spend their days refining liquid-food solutions for prepared foods, plant-based foods, and dairy products. At the heart of her role is helping engineers design processing lines to deliver tasty products that satisfy customer demands and consumer desires.
“A product can change in many ways; the degree of that change is often where the nuances of processing lie.”
Equally important is balancing taste with food safety and sustainability – a tricky task when food processing transformations range from subtle alterations to complete reimaginations.
Whether it's transforming milk into a creamy delight or turning fruit into fresh juice, processing is a delicate balancing act between maintaining a product's natural integrity, ensuring food safety and being efficient with energy and resource consumption.
“A product can change in many ways; the degree of that change is often where the nuances of processing lie, so my job requires a high level of precision,” Helena says.
Food processing must become more sustainable
To address the growing emphasis on sustainability in the industry, Helena and her team are increasingly focusing on optimising processing techniques.
“Many of our customers come with problems they need help solving. Sometimes, their product is already on the market, but they want to change their equipment without overhauling their complex process,” Helena says.
“We want that fresh experience from juice, even if we drink it a week or a month from now.”
Or perhaps they want to completely change the technology they use, opting for more efficient techniques.
“More and more, I’m focusing not only on getting the right processing line and equipment for a customer but also on considering how we can produce a product with the lowest energy or water use.”
This is a symptom of positive change, she says, and with the food and beverage industry working to implement more efficient practices, both processing techniques and recipes have to change.
Finding a safe way to make tasty milk and juice
With milk or orange juice, Helena explains, the goal is to change the product as little as possible, so here, the technique takes precedence over the recipe.
“We want to treat it to make it safe, but at the same time, change the taste or texture as little as possible,” Helena says. “We want that fresh experience, even if we drink it a week or a month from now.”
With milk, that often means applying the right amount of heat. Various techniques can be used, including pasteurisation, where milk is heated to kill bacteria and extend shelf life to a week under chilled conditions.
“Many customers want to be able to store milk at room temperature for up to nine months. To do this, we use what we call UHT (ultra-high temperature) treatment for a short time,” Helena explains.
UHT is a process that requires toeing a fine line: while heat kills bacteria, it also affects the milk by changing its chemical composition.
“The key is that the chemical changes are more dependent on the duration of the heat treatment than on any specific temperature. One of the main benefits of UHT is that the high temperature can kill the bacteria while minimising chemical changes because the treatment is fast,” says Helena.
“More and more, we focus on how we can produce a product with the lowest energy or water use".
On the energy side, pasteurisation is more energy-efficient in terms of the initial heating process. Still, UHT treatment can often be more sustainable when used for the right products because it offers a longer shelf life and doesn’t require energy-intensive refrigeration.
“We help customers decide on the best process depending on different factors like logistics, storage possibilities and consumption patterns,” explains Helena.
Seeking compositional change with advanced processing
Sometimes, achieving a perfectly delicious product means you intentionally have to change the composition of a product.
Take creamy rice pudding, for example. To prepare it at home, you would typically cook it in a pot – but this doesn’t generate the shelf life most consumers demand. Rice pudding requires an additional heating step in order to achieve this.
“Heat treating it after preparation is not the best option because it negatively impacts the quality,” says Helena. We try to optimise processing lines for preparing and sterilising simultaneously because sterilisation on its own would change the product in a way we don’t want it to.”
Injecting milk, rice, and sugars into a pipe and allowing them to mix and prepare while flowing towards the final heating step is both more efficient and gentler on the product. It demands precise temperature control, and sometimes, you need pipes that are several hundred meters long to ensure the rice swells to the right degree.
“This is exactly what my job is about – engineering and food technology working perfectly together,” Helena explains.
A similar method is applied to other products like vegetable soup. Just like cooking at home, you chop everything, season it, and cook the soup before eating it. The challenge is that prepared foods need to be packaged after they’re prepped – and they often need to be able to last up to six months.
“Our job is to ensure the right shelf life and that the particles are evenly distributed in each package. We pre-cook vegetable soup just enough that it’s not quite ready to eat but has the optimal texture once it’s sterilised. Then it’s ready to be enjoyed cold or after heating at home,” says Helena. “You could say we take it as far as possible, calculating the sterilisation process as part of the preparation to make it the perfect shelf-stable product.”
Innovating and experimenting with recipes and technologies
Innovation plays a crucial role in meeting both quality and sustainability goals.
“In some cases, we need to make small changes to the recipe,” she says. “But we can usually get it right by experimenting with different heating technologies and processing parameters like homogenisation.”
Right now, Helena is working on a project where the goal is to find a way to get a new dessert to thicken in the package instead of the processing line.
The idea is that when the product is packaged, it should not yet be thick – beginning to thicken, instead, after a day or two in the package.
“It’s easier to package a product that is thinner and smoother,” she explains, “so this helps minimise processing time, saves energy, and, with a lower volume in the processing system, also saves water and detergent.”
The future of food processing is complex – and full of opportunity
Looking ahead, Helena sees a meeting of obstacles and opportunities. On the one hand, innovations like the product thickening in the package and areas like plant-based surging point towards a more complex future of food processing.
“There are so many customers who have a great product that we can help produce even better, saving energy and water and improving the quality.”
But where there’s a challenge, there’s also a world of possibilities for those who are ready to step up. Helena is excited to adjust, optimise and develop new processing methods that can deliver the perfect balance between taste, safety and efficiency.
“It’s really a passion for me to help customers optimise their lines and find the best version of what they’re looking for,” Helena says. “There are so many customers who have a great product that we can help produce even better, saving energy and water and improving the quality. That’s what drives me.”
