Epicurean Horizons

How Genetically Engineered Yeast is Pioneering the Flavours of Tomorrow

A. J. Li

IN THE EVER-EVOLVING WORLD OF GASTRONOMY, where tradition and innovation dance together, a new player has taken centre stage – genetically engineered baker’s yeast. The same yeast that has been used to bake bread and ferment wine for millennia is now being used to revolutionise the way we develop and produce flavours, all thanks to some ingenious genetic manipulation. It is now only a matter of time before its full potential is harnessed to produce existing flavours more easily and cheaply, as well as to create entirely new taste dimensions that were once only found in science fiction.

But scientifically speaking, what exactly is flavour? The distinctive flavours of particular foods are predominantly caused by certain chemical compounds found within them. For example, vanillin, a molecule made up of an arrangement of carbons, hydrogens, and oxygens, is the compound responsible for the unique flavour of vanilla. Since a single molecule is responsible for the flavour of the vanilla bean, scientists can replicate the flavour by synthesising it in a lab. The first such recorded case of flavour being synthesised and used was in 1851 at the Crystal Palace exhibition in London, where sweets were artificially flavoured to taste like apple, pear, grape and pineapple, with the flavouring compounds having been synthesised in a lab. 

So if the technology to create artificial flavours has existed for centuries, why then is yeast so important? Synthesising molecules in labs is notoriously complicated and precise, particularly for some specific flavours, making it difficult to scale up production as much of the work is done by scientists. Yeast, on the other hand, can be genetically engineered to produce almost any molecule, with the yeast itself doing all of the work creating the flavour molecule as it ferments, making this method of production comparatively more simple and scalable.

Yeast produces these flavour molecules as a byproduct of its metabolic activities during fermentation. Scientists can manipulate the production of these byproducts by introducing specific genes or pathways into the yeast’s genetic code, steering yeast metabolism towards producing certain molecules. To create these specific flavours, scientists identify the genetic code that produces the flavours in a fruit or flower and insert it into the yeast. This method of production is a relatively new technology when compared to lab synthesis methods because the necessary gene sequencing technology has only become available in the past decade. With the rise of genetic databases, computing power can now be used to discover more efficient or successful pathways for genetically engineering yeast.

Using this method to produce flavours has many benefits. Perhaps some of the most important upsides to this technology involve its ability to save money and effort. Take vanilla as an example. Vanilla is the most labour-intensive crop in the world, taking around one year to go from growth to export. It is a particularly demanding crop, requiring hand-pollination during an extremely short flowering window which infamously lasts a single day before it becomes too late. Furthermore, the primary location where vanilla beans are grown is on the island of Madagascar, which is highly prone to natural disasters such as cyclones. This can destroy entire crops and further drive up the price of vanilla which at one point cost more than silver by weight. Yeast can be genetically engineered to produce vanillin, the aforementioned molecule responsible for the distinct vanilla flavour, reliably, easily, and at a fraction of the cost. Considering how ubiquitously vanilla is used to flavour products, the advantages of this method of flavour production become apparent.

A potential caveat, however, of this technology that may hinder its integration into commercial food production, is the stigma surrounding genetically modified organisms (GMOs). As long as the public continues to be sensitive and distrustful of GMOs, food companies will hesitate to adopt methods of production involving genetically engineered yeast. In the case of bioengineered yeast, the flavour molecules produced during its fermentation are often chemically identical to the actual molecules produced by plants or flowers, making products that use this method of flavouring indistinguishable from “all-natural” methods. Furthermore, many major health organisations, including the World Health Organisation, endorse the view that GMOs pose no health risk. The stigma surrounding GMOs must be broken down if the full potential of ground-breaking technologies such as genetically engineered yeast is to be harnessed. Indeed, the most exciting future prospects for flavouring come from GMOs as entirely new flavours, which are unavailable in nature, may be researched and developed.

Genetically engineered yeast promises to revolutionise traditional methods of flavour production, broadening our Epicurean horizons. As we blend the artisanal with the scientific in exploring this captivating frontier, one thing is certain: the future of flavour holds endless surprises, and it all begins with a humble yeast cell.