Could electrochemistry slash sweetener production costs?
US-based biotechnology firm Dynamic Food Ingredients (DFI) is in talks with food manufacturers about commercialising a technology it claims could slash production costs for xylitol and erythritol by using electrochemistry.
DFI, a spin-off from Purdue University in Indiana, has applied for a suite of patents to protect its discoveries and is confident of striking a deal in the coming months.
Chief technology officer Jonathan Stapley said: "We've been talking to a number of companies about scaling this up to produce these sweeteners on an industrial scale, possibly from the same facility."
Typically, xylitol is produced through the hydrolysis of birch wood or beech wood. Key manufacturers include Danisco, Roquette, Cargill and several Chinese firms. However, this technique typically involved the use of "acids, high pressure and temperature, chemical catalysts, and several separation and purification steps", he claimed.
More recently, manufacturers have also explored other approaches, including metabolic pathway engineering, to retool the enzyme-making machinery of E. coli bacteria so they can convert xylose and arabinose into xylitol. Using this technique, bacteria are kept inside biofermentors and fed a 'broth' of corn fibres or other raw materials. The xylitol they excrete then has to be purified from the broth.
But this technique was also inefficient, claimed Stapley. "We can transform starch or sugar into xylitol on a one-to-one molar basis. The only by-products are hydrogen, oxygen and bicarbonate, and our process takes hours, not days."
He added: "Electrochemistry is well known for treating water or making chlorine. But there hasn't been an industrial-scale application in food before."
DFI's technique involves passing raw materials through an electrolytic cell, he said. "It's like electrodialysis of wine."
Potentially, the technology could slash the price of both xylitol and erythritol, he claimed. "Price and supply are what has kept this market back. For example, if you had a US manufacturer that wanted to use xylitol in a national roll-out, that could take up the entire world's supply.
"Our conversion efficiencies are extremely high, so we can accommodate production rates far exceeding those of other technologies. Likewise, some of the raw materials the main manufacturers use are also in short supply, unlike starch, which is pretty ubiquitous."
However, Danisco, which has just expanded its xylose factory in Lenzing, Austria, rejected claims that its production process was inefficient.
Business director Dr Juho Jumppanen said: "If you were only getting xylitol out of birch wood, yes, it would be inefficient, but we are extracting a whole load of other sugars from the by products of the process as well, from D-mannose to L-fucose and D-galactose. In fact, of every kilo of raw material, I'd say 99% of it goes into end products."
Danisco was always open to new technology, but had not so far identified anything superior to the producton method that it was currently using for xylitol, he said. "Setting up a new facility can cost £100M, so it's not something you do lightly."
