A research-industry partnership between the John Innes Centre, the Quadram Institute, the University of Bristol, and LettUs Grow has used aeroponic techniques to grow pea shoots fortified with Vitamin B12, delivering the recommended daily allowance in a 15-gram serving.
© LettUs Grow
Research findings
The fortified salad crop exceeded expectations by delivering in excess of the RDA of Vitamin B12 in a single serving. The team also found that the pea shoots maintained their shelf-life and the B12 content persisted through an extended period of cold storage, elements essential for the crop to succeed commercially.
The research, published in Communications Biology, offers a commercially viable approach for dietary supplementation of vitamin and nutrient intake predicted to work not only in pea shoots, but in other rapid-cycling salad crops grown in indoor farming environments.
Simulated human digestion experiments carried out at the Quadram Institute confirmed that the fortified pea shoots are accessible to digestion, meaning the vital nutrient will likely be passed into the bloodstream of those eating it.
The B12 problem
Vitamin B12, also known as cobalamin, is an essential nutrient that plants do not produce and which presents a nutritional insufficiency risk for people adopting vegetarian and vegan diets without supplementation. Symptoms of deficiency can include anaemia, muscle weakness, and psychological, cognitive, and neurological problems.
The most structurally complex nutrient, Vitamin B12 is made exclusively by bacteria. Humans acquire it from animal-based foods including fish, meat, poultry, eggs, milk, and dairy products. Around six percent of the UK population is B12 deficient and a further 44 percent may have insufficient levels. Globally, B12 insufficiency is common, particularly in populations consuming low amounts of animal-derived foods and in older adults.
Tablet-based supplements are widely available, but carry drawbacks: they are easily forgotten and are less effective when taken without food, as eating releases enzymes required for nutrient absorption. Many people also prefer to receive nutrients through whole foods rather than supplements.
Hidden hunger
The project addresses the broader issue of hidden hunger, where people receive enough calories but not the right mix of nutrients to maintain good health. The term also applies to nutritional deficiencies that may occur in people taking appetite-suppressing drugs.
One obstacle has been the prohibitive cost of producing Vitamin B12 commercially. Its molecular complexity makes traditional chemical synthesis impossible, requiring vast quantities of bacteria to produce. The vitamin costs up to £20,000 per kilogram, roughly one third of the price of gold. Around 90 percent of the world's B12 supply is currently produced in China.
How the system works
The team used aeroponic technology developed by LettUs Grow to supply pea shoot roots with a B12-fortified nutrient solution delivered as an aerosol. A thin film of nutrients forms on the roots, and the vitamin is absorbed and taken up by the plant's nutrient transport system.
During an eight-day cultivation period, plants were supplied with cyanocobalamin, the most widely available and bioavailable form of B12. Harvested plants accumulated more than the quantity required to deliver the RDA within 15 grams of plant material. The aeroponic method enables precise control over the application of expensive source vitamins, improving efficiency and reducing cost for commercial partners and consumers.
"This novel fortification method can be done at extremely low cost to growers as a way of providing consumers with a cost-effective way of supplementing their diet with Vitamin B12 in a form that their body can use," says Professor Antony Dodd, group leader at the John Innes Centre and corresponding author of the study.
Commercial viability
The team estimates the additional cost of adding B12 to bags of pea shoots could be less than one penny per unit. The team is now investigating commercial routes to market and adapting the technique for use in both vertical farms and horticultural glasshouses.
"The beauty of this work is how it marries high tech and low tech in such a cost-effective way. Pea shoots are literal sponges for B12, while vertical farms provide a controllable environment in which we can tailor its uptake by the plants," says Dr Bethany Eldridge, first author of the study. "This method diversifies ways of getting B12 naturally into your diet, especially if you are not consuming meat and dairy. Globally B12 levels are in decline and if we can find a variety of ways that we can get it into food in a bio-accessible way, then that is exciting."
"The challenge we faced is to find a way to provide a bioavailable source of Vitamin B12 in a vegetarian meal. The solution came not through engineering the plant but by simply exploiting the ability of the plant to take up B12 when applied," says Dr Jonathan Clarke, Head of Business Development at the John Innes Centre.
"Vitamin B12 deficiency is often framed solely as a concern for people following vegetarian or vegan diets, but the reality is far broader. Developing practical ways to incorporate B12 into everyday foods offers an exciting route to improve nutritional resilience," says Professor Martin Warren, Chief Scientific Officer at the Quadram Institute.
What it means for indoor farming
"The exciting thing about this project is that it is the first time the enhanced yield potential of aeroponics has been combined with the nutrition enhancement of B12 fortification in a way that can be scaled up to commercial volumes," says Jack Farmer, Head of Research and Development at LettUs Grow.
Source: John Innes Centre
