Sustainable food production

Plant-based foods that don’t taste like cardboard

For consumers to embrace plant-based dairy and meat alternatives, they need to be appetizing. Researchers at DTU are working hard to develop ingredients and production methods that can lead to tasty and nutritious foods with a reduced carbon footprint—and they are making good progress.

Field of peas. Photo: Colourbox — Researchers are busy in the laboratories where they work to transform crops such as peas grown in Denmark into appetizing alternatives to meat and dairy products. Photo: Colourbox

Tuesday 01 October 2024

Miriam Meister

For the planet to sustainably feed a growing population, much of the world needs to turn to a more plant-based diet. However, many food producers struggle to produce good, nutritious, plant-based alternatives to, e.g., dairy products that appeal to consumers.

At DTU Lyngby Campus, microbial biotechnology experts are working with researchers and industry to find the recipe for fermented plant-based drinks with a protein content like cow's milk (approx. 3.5 per cent). REPLANTED, as the project is called, is funded by the AgriFoodTure partnership and focuses on crops that can be grown in Denmark, namely peas, oats and potatoes.

Taste is key

“The problem with many plant-based drinks is that they have a bit of a cardboard box flavour,” Senior Researcher Claus Heiner Bang-Berthelsen says, thereby touching on a sore point.

In a survey conducted by YouGov for the organization, Danish Industry in the spring of 2023, 30 per cent of respondents pointed to taste as standing in the way of eating plant-based food. Taste is thus the biggest barrier, while 27 per cent said that habits keep them from doing so.

“In our work, we have managed to identify microorganisms that we can add to the plant-based drink to convert a lot of the naturally occurring molecules that are known to cause those off-flavours into other molecules with much less off-flavour,” the senior researcher explains.

The project has also identified microorganisms that can be used to convert components in the plant drink that otherwise prevent the body from absorbing the protein in the drink.

“Because if the plant drink contains something that blocks the absorption of protein, then we're back to square one,” Claus Heiner Bang-Berthelsen emphasizes. Once the right mixing ratio for the plant-based drink is in place, the researchers will focus on developing the optimal blend of lactic acid bacteria in a starter culture that can transform the drink into a plant-based yoghurt alternative.

Three containers containing a plant-based yoghurt alternative, liquid from the production of beer and soya drink respectively. Photo: DTU — Over the years, researchers at DTU Food have experimented with different side streams in the production of plant-based foods. In this case, mash from beer production was used to make a yoghurt alternative. Photo: DTU

Still milk in the cheese

The DTU researchers are also working to produce plant-based cheese alternatives—or rather hybrid products. Because it's something of a mystery how to make a product that resembles the familiar cheeses without using animal-based raw materials, the senior researcher explains and continues:

“It's almost impossible to make a plant-based cheese that has a reasonable nutritional composition, but also a flavour similar to what we know from animal products. So, we're trying to find a cheese that's 50 per cent plant-based, so we can greatly reduce the carbon footprint.”

Good progress is being made: There are e.g., promising prototypes in the pipeline for an alternative to feta-style cheese cubes, which are similar in texture and shape to the well-known variant made exclusively from cow's milk. The prototype has been developed in a PhD study in collaboration with dairy company Thise and the University of Copenhagen with funding from the Danish Dairy Research Foundation.

According to Kristian Albertsen, Senior Advisor at Thise, there is great value in collaborating with researchers who generate important insights into e.g., characterizing the proteins in the plant-based ingredients, how the proteins coagulate, and ways to remove off-flavours in the product.

Thise is keen to meet consumer demand for more plant-based products, and Kristian Albertsen thinks the feta-style cheese cubes could be a good addition to the company’s product line:

”There's a long way to go, but if it tastes good and the price is right, we'd love to have these kinds of products on the shelves.”

Facts

About plant-based drinks

All plant-based milk alternatives—whether made from legumes, nuts, seeds or grains—have less impact than cow's milk in terms of greenhouse gas emissions as well as water and land requirements researchers from Curtin University in Australia have concluded following a review of existing studies.

A study from DTU shows that in 2021, Danes bought seven times as much plant-based drinks as in 2007. However, purchases still amounted to very little: In 2021, the per capita consumption was one glass of plant-based drink every two to three weeks—compared to eight to nine glasses of cow's milk per week. The study is based on purchasing data from Euromonitor.

Source: Curtin University og DTU

From waste product to food

The researchers' work does not only focus on milk alternatives. The GUDP-funded project MycoProtein, which is a collaboration with the University of Copenhagen, has developed a product with a flavour and nutritional content similar to that of meat—without having been near a barn.

During the project, the researchers have identified fungi that grow freely on tree trunks in Danish forests. In a fermentation process they can grow in waste products from e.g., sugar beet processing or beer brewing.

“These fungi are very good at breaking down long chains of sugar molecules in the waste products, which they use to form mycelium,” Claus Heiner Bang-Berthelsen explains.

Mycelium is a network of fungal threads. When fungi grow in nature, mycelium is the part that grows underground, beneath the part that we know as mushrooms. However, mycelium can also be produced in a steel tank.

The researchers’ work has shown that the studied fungi are non-poisonous in all studied growth media. The mycelium produced is relatively bland, but it has an appetizing texture and contains fibre, protein, vitamins and minerals.

Mixed with other ingredients such as onions, garlic and spices or flavourings it is a promising meat alternative. However, there is still a long way to go because getting new foods risk assessed and authorized in the EU is a lengthy process.

"Food should of course be safe to eat. But it would be desirable to have a more agile process so that producers have a greater incentive to make innovative foods that benefit the climate and hit the shelves faster,” Claus Heiner Bang-Berthelsen explains.

A setup with laboratory flasks for fermenting mycelium and small 'meatballs' made from the mycelium. Photo: DTU — DTU researchers view mycelium grown on residual products from e.g. sugar beet processing as a promising, nutritious alternative to meat. Photo: Sanne Kjærulf Todorov

Facts

Sustainable food

26 pct. of the world's total CO2 emissions come from food production. Livestock in particular account for a large share.

To reduce the climate impact of food production, we need a green transition. This can be achieved through the use of technology, digitalization and the development of new foods.

Contact

Claus Heiner Bang-Berthelsen Senior Researcher Mobile: +45 29866900 claban@food.dtu.dk