Precision Fermentation: Past, Present, and Future Promise

Microorganisms and fermentation have been crucial for food safety and flavour for thousands of years. Find out how precision fermentation is opening new avenues for the future of sustainable food production.

To understand precision fermentation, we need to start with good old-fashioned fermentation itself.

Fermentation is a simple age-old technique that harnesses the power of microorganisms to transform and preserve food. In the absence of oxygen, microbes do this by feeding on glucose or other sugars, breaking down large, often less flavourful molecules into smaller, more flavourful ones. This process enhances food's nutritional and functional properties, changes taste, and even prevents spoilage.

For example, during yoghurt production, lactose (a complex sugar) is broken down into lactic acid. This makes it more easily digestible, gives it that tangy taste, and prevents other microorganisms from growing due to low pH. A few other fermented foods you will likely be familiar with include beer (fermented barley, hops and water), wine (fermented grapes), and kimchi and sauerkraut (both from fermented cabbage). Today, fermented products represent a significant proportion of all diets worldwide, accounting for as much as one-third of food intake.¹ 

Fermentation is also one of the earliest forms of ‘biotechnology’. It has evolved from a spontaneous natural process, possibly due to accidental contamination, to a more controlled environment, in oak barrels or stainless-steel tanks and using specific starter cultures like Penicillium camemberti or Saccharomyces carsbergensis. Precision fermentation is the next, most technologically advanced step in this evolution.

Find out more about the process behind fermented favourites like kombucha and kimchi.

How does precision fermentation work?

During precision fermentation, a specific microorganism produces an organic compound under tightly regulated conditions. This compound is then separated, purified, and utilised, either in its pure form or as an ingredient in various other products. 

To illustrate this, consider the production of beer. In traditional fermentation, yeasts ferment a mixture of barley, hops, and water, and all the fermented liquid is collected, filtered, and consumed. In precision fermentation, the focus shifts to separating just one compound from beer, such as isoamyl acetate, an ester responsible for a distinct banana flavour.² This flavour can then be added to other foods, such as my least favourite banana-shaped gummies. 

In industrial beer production, everything is tightly controlled to produce a distinct percentage of alcohol, bitterness, smell, and taste. Additionally, selecting the ingredients like hops and yeast is crucial. This attention to detail also applies to precision fermentation, as different microbes can produce distinct compounds.

Microorganisms can be “forced” to create substances not naturally found in them by changing their genes. For instance, to make the main protein in egg whites called ovalbumin, scientists insert the gene responsible for ovalbumin into the DNA of a microorganism. This makes the microorganism produce ovalbumin, along with its own proteins

A versatile solution - treating diabetes to making cheese

Although the term “precision fermentation” was coined recently, using microorganisms as tiny production factories dates back to the 20th century.

Insulin use in the pharmaceutical sector for diabetes treatment is one of the earliest examples of this. In the past, those with diabetes faced limited options for treatment, often restricted to strict low-carbohydrate diets as the most effective approach. After its initial discovery in a dog pancreas, insulin extracted from cattle started being used to treat diabetes in 1922.⁵

However, by 1981, one pound of insulin required 8,000 pounds of glands from 23,500 animals, which was enough for just 750 patients. Thanks to precision fermentation, a bacteria, E. coli, could be used to produce insulin more cheaply and reliably. This approach not only addresses cost and supply concerns but also allows for the creation of different insulin variants (e.g. fast or slow release) tailored to the specific needs of individual patients while simultaneously eliminating the allergies that some people with diabetes experienced with animal-derived insulin products.

Top: Dr. Frederick Banting and Charles Best who, in 1921, successfully isolated the hormone insulin for the first time.

Bottom: Scientists in a research lab in South San Francisco, 1982. Their combined effort in genetic engineering resulted in the first artificially produced human insulin, synthesised using E. coli. Photo: Getty. 

The food industry also witnessed a significant precision fermentation breakthrough in the late 20th century when the Food and Drug Administration approved genetically engineered chymosin, an enzyme essential in cheese-making - traditionally found in rennet. Originally extracted from calf stomachs, precision fermentation introduced a purer yet equally functional enzyme variant with a more consistent activity and less of a price fluctuation than animal-derived preference. Plus, it’s suitable for vegetarians.

It is now widely used in the US and many other parts of the world, with the rennet from precision fermentation accounting for up to 80% of the global market share. Although, some traditional cheesemaking still enforces obligatory animal-derived rennet.⁶

The egg without the chicken

In a more contemporary context, precision fermentation also allows us to create certain proteins, such as that from milk and eggs, but without the need for animals. For example, several companies make proteins which are biologically identical to what you’d find in whey, casein (traditionally from milk), or ovalbumin (egg white's primary protein). Once the microorganisms are equipped with genetic instructions, they act like tiny protein factories, producing the desired proteins as part of their natural processes. This biotechnological approach offers a sustainable and more efficient way to manufacture the proteins found in traditional dairy and eggs. This can help us address the environmental, social and ethical concerns around industrial-scale dairy and egg production.⁷

Find out more about the impact of beef production

The next generation of fats, sweeteners, flavouring, and colourants are also evolving alongside precision fermentation, representing a promising avenue for making food production more sustainable thanks to lower land use, energy requirements, water consumption and greenhouse gas emissions.⁸

However, precision fermentation comes with its fair share of challenges. These include regulatory concerns surrounding genetically modified organisms (GMOs), consumer distrust of food grown in a lab, and the need for thorough safety assessments for novel foods. Additionally, the high cost of implementing precision fermentation technology poses economic obstacles. If we can overcome these challenges, the potential benefits of precision fermentation include reducing the environmental impact of agriculture and strengthening global food security for a growing population.⁹