Right now, says Debut Bio’s co-founder and CEO Dr Joshua Britton, you can extract colors, flavors, and bioactives from plants, which can be expensive, inefficient, and not very sustainable if you’re devoting acres of agricultural land to grow plants that only contain trace levels of these ingredients in a growing cycle that might take months or even years.

As a result, more companies are now using synthetic biology to engineer microbes to express food ingredients from flavors to collagen in big fermentation tanks filled with sugary feedstock.

‘Bacteria and yeast have been the workhorses of industrial biomanufacturing for years. Unfortunately, these bio-factories have their drawbacks’

But microbial fermentation can’t produce everything the food industry wants, said Britton: “Many of the great ingredients we find in nature are too complex to be made inside a ​[yeast/bacteria] cell, so they’re still being extracted from fruits or insects ​[eg. cochineal].

“Some carotenoids can be made from microbial systems ​[eg. the orange colorant beta-carotene can be made by a filamentous fungus called Blakeslea trispora​], but there are lots of other carotenoids and other natural colors that can’t be made this way, so they are still extracted ​[from plants] or produced via chemical synthesis.”

Microbial fermentation systems also presents certain challenges​ including low yields and high purification costs (target ingredients are either secreted into the tank, and require subsequent purification, or locked within the cells, requiring an extraction process), he added.

“Bacteria and yeast have been the workhorses of industrial biomanufacturing for years. Unfortunately, these bio-factories have their drawbacks; reaction times can be slow, the product and starting material have difficulty passing through the cell wall, and each cell must be reprogrammed to produce a new molecule. They also use a batch process.”