Sugar is one of the world’s most glorious ingredients. Deliciously sweet, it brings flavour and texture to so many of the dishes and products we love. But as we all know, sugar has a dark side. Alongside health issues like obesity, diabetes, and tooth decay, sugar is a volatile and highly political commodity. Over the years, alternatives like artificial sweeteners, corn-based sweeteners, and even other natural sweeteners like honey or maple syrup have cropped up to try and combat some of these issues, but they all have their drawbacks as well. Now, there is a new prospect, a group of sweet proteins that promise to bring sweetness without strife.
Sweet proteins are natural proteins, most of which have been discovered in plants in the tropical rainforest.[i] These proteins are hundreds or even thousands of times sweeter than sugar and, as such, far less volume is needed to achieve the sweet flavour. But since these proteins occur in such tiny concentrations (think <1%) in the plants that produce them, extracting them to serve the 20-million-ton US sweetener market is hideously expensive, extremely time-consuming, and terribly destructive.[ii] Just one sweet protein, called thaumatin, has been extracted at scale and used commercially. Today it can be found in products like chewing gum, dairy, and pet food since earning approval in 1985.[iii]
But there are many more that have been discovered and isolated since then. Brazzein, Monellin, Miraculin, and Mabinlin are just a few of the sweet proteins that show promise for use in the food industry.[iv] These proteins are particularly interesting because although they share many of the positive attributes of the sweeteners we know and love, like masking sour and bitter flavours, adding sweetness, or providing bulk, they tend to have no adverse health effects, no unpleasant aftertastes, and possess unique functional properties for different applications. So far they haven’t been fully exploited because they have been too hard to extract, but with the availability and decreasing cost of Precision Fermentation (PF), producing these natural proteins at commercial scale is becoming not just possible, but likely lucrative.
Because they are produced using PF, there is also significantly more customization available. Producers can design proteins by altering the genetic code in such a way that suits the protein for a specific use, and they can do this cheaply and at scale. Many companies have jumped at the opportunity to start producing some of the known sweet proteins while others have been busy designing new ones.
Joywell Foods, for example, is a food tech company that produces known sweet protein miraculin. Miraculin is known as a taste modifier which means it has the ability to modify your taste receptors and affect the way you perceive the flavour. Kraft foods recently led a $6.9 million funding round into Joywell foods which is particularly exciting because if properly exploited, they could be superior to sugar in masking unpleasant, very sour, or very bitter flavours. [v] This is especially useful for a food industry that has been trending towards super healthy foods like turmeric or seaweed that have strong and potentially off-putting flavours.[vi]
Amai Proteins, another food tech company, has teamed up with Ocean Spray to reduce the sugar content in their cranberry juice by 40% by creating a custom sweet protein produced by PF. This enables Ocean Spray to offer low-calorie (diet) options of their beverages without compromising on taste.
There are even a few examples of molecules that are not proteins per se but are still being developed and used in the same way. Avansya, a joint venture between food giant Cargill and Royal DSM, makes EverSweet™ stevia sweetener in this way. Stevia is a natural sweetener that comes from a plant but many people find has an unpleasant aftertaste. Avansya uses PF to produce only the relevant molecules, glycosides called Reb D and Reb M, from the stevia leaf which eliminates the aftertaste while also making the production process drastically more efficient.[vii], [viii]
MeliBio, a start-up in San Francisco is developing a PF process to replicate the compounds found in honey, right down to the specific aroma and flavour compounds found in the flowers of any particular region. Innovation like this is not only beneficial to human health and food preference but also will have seriously positive implications for the environment.[ix]
While the production cost of products made using precision fermentation is on track to meet the cost of sugar (glucose, not table sugar) by 2030, the disruption of sweeteners could happen well before that. This is because sweet proteins are not a 1:1 replacement of sugar because of the lower product requirement and extra functionality. The possibility space for sweet proteins is enormous if these proteins can really match or exceed the flavour and texture quality of sugar and other caloric sweeteners with no drawbacks. With competition like this, not only will the food industry be available for the taking, but so will every other industry that needs a little sweetness.
 Honey production places significant pressure on wild and native bee populations as commercial honeybees compete with them for food. Wild and native bees act as pollinators, a process that is crucial to food production (i.e., most of our fruits and vegetables) and ecosystem health.
[vii] (2019, November 14). Cargill-DSM joint venture Avansya starts commercial-scale production of EVERSWEET™ stevia sweetener, as consumers increasingly demand reduced-calorie food and beverages. Avansya. Retrieved from here.