Fermentation targets more eco-friendly ingredients

Plant extracts like natural sweeteners and antioxidants make up a tiny fraction of the plants from which they are derived, meaning a relatively large land and water footprint. Could producing these compounds via fermentation be more environmentally and socially responsible?

Using fermentation of engineered yeast, companies are already producing ingredients like stevia extracts, resveratrol, and even animal-free dairy products that are identical to their nature-derived equivalents. The process works by modifying yeast to have enzymes that produce a precise target compound when fed glucose and nutrients.

Although the yeast is modified, companies working in the area are keen to stress that the process does not result in genetically modified ingredients as the yeast is completely removed and doesn’t end up in the final product. In fact, the resulting ingredient is indistinguishable from that produced conventionally.

Theoretically, there is no limit to which molecules can be targeted, but it is expensive and time-consuming to figure out how to reach the target compound in the first place, and it is difficult to scale up, meaning that ingredients made via fermentation tend to be expensive. That is why many companies specialised in making ingredients in this way focus on niche ingredients, such as those that are expensive and labour intensive to produce, and those that are difficult to source in large quantities.

Swiss-based Evolva Holding is one company that specialises in such ingredients, with a portfolio that includes flavours like vanillin, the red wine antioxidant resveratrol, and sought-after aroma compounds from orange (valencene) and grapefruit (nootkatone), for which demand outstrips supply. One kilogram of nootkatone, for example, requires 400 tonnes of grapefruit to produce. It can be used as a flavour, fragrance or even as a highly effective insect repellent. Growing such ingredients in the lab clearly has potential to extend their use, while using sugar and yeast to produce targeted compounds saves an enormous quantity of water, as well as precious agricultural land.

And the environmental benefits of fermentation-derived ingredients increasingly have entered the narrative. Perfect Day, for example, is a US-based producer of animal-free dairy proteins, which highlights the environmental cost of animal agriculture, and describes its products as having “less impact on the earth”. In summer 2019, it launched three animal-free ice cream varieties, and it has inked a deal with ADM to produce more dairy-free milk ingredients on a large scale.

Zero-calorie plant-derived sweeteners are the holy grail for many food and drink companies, making them another major target area. Natur Research Ingredients and Magellan Life Sciences both make a brazzein sweetener through fermentation, allowing it to make much larger quantities of the sweet protein than are found in nature. Brazzein comes from the West African oubli plant, but extraction is expensive – and naturally available quantities of the sweetener are insufficient for commercial use. What is more, cultivating the oubli plant is prohibited by biodiversity laws so scaling up via traditional agriculture is not possible.

Also in sweeteners, Evolva is working with companies like Cargill and DSM to produce some of the most sought-after sweet compounds in stevia via fermentation.

This process raises a problem for food companies, however: is an ingredient that is developed in the lab equivalent to one from nature, even if it is identical on a molecular basis? Ultimately, the answer depends on why the individual seeks naturally derived ingredients in the first place. If they are looking to make choices that respect the natural environment, the lab-grown ingredient could indeed be the more responsible option.