Natural colors are improving all the time, and several firms are now developing reds through microbial fermentation including Michroma (fungi), Phytolon, Impossible Foods and Motif FoodWorks (yeast) as well as more traditional plant sources such as sweet potato, beets, purple carrots and tomatoes.
However, delivering a heat-stable, light-stable, naturally derived, vibrant red hue in products with neutral to higher pH remains very challenging if you want to avoid crushed cochineal insects, which are not vegan, vegetarian, halal or kosher, and can put buyers off.
Tomato lycopene work well in dairy, for example, but it’s not the kind of rich deep vibrant red you’d need for a red velvet cake; while beets – which can have an earthy flavor – work at a neutral to basic pH ranges, but are not very heat stable, and can turn brown.
Meanwhile, anthocyanins from grape skin and juice, elderberry, purple and black carrots, purple sweet potato, red cabbage and red radish can work well in lots of applications such as beverages, but can change color from red to purple to blue if the pH starts to rise.
‘Some colors are really difficult to make in the cell, or you can make them in a cell but you have to ferment a million liters to make a couple of hundred kilograms’
To make its vibrant reds, Debut Bio first deploys a fermentation process whereby a micro-organism eats sugars and turns them into a valuable intermediate.
The next step deploys a ‘cell-free’ approach where Debut deploys some of the machinery of cells such as enzymes, nature’s tiny biological catalysts, and immobilizes them (essentially fixes them in place) to make a 'wall' of enzymes through which it can flow the intermediate, and a vibrant red color then comes out the other side, explained co-founder Dr Joshua Britton.
Under the second, two-year long, multimillion dollar phase of a joint development agreement with DIC, Debut will develop vibrant reds for the food, nutrition, and cosmetic industries, after a successful collaboration during the past year, wherein Debut Biotech achieved titers 1,000x higher than traditional fermentation methods deliver, claimed Britton, who is currently commissioning pilot production in San Diego.
“Some colors are really difficult to make in the cell, or you can make them in a cell but you have to ferment a million liters to make a couple of hundred kilograms. So switching to cell-free where we boosted the titers 1,000 fold was far more appealing.
“The red is stable to heat, light, pH, and things like pasteurization and UHT or spray drying.”
‘This has unlocked a whole new market for us’
So who is doing what in the partnership?
According to Britton: “Debut Bio is handling all the technical, pilot, and the FDA color additive petition side of things [with a plan to submit in 2023] and DIC will handle sales and marketing and global penetration.”
If everything goes to plan, the red should be at commercial scale in 2024, he said.
“This has unlocked a whole new market for us, and we are talking to other companies about other classes of natural colors. Some colors and bioactive ingredients are too expensive or unsustainable to extract from plants, but can never be made inside a single-celled microorganism [such as yeast or fungi cells], which is where cell-free comes in.”