Gluten-free bakery companies are struggling with the soaring price of rice flour as rice stocks hit a 30-year low.

The price of a tonne of rice has increased from around £200 to £500 since the turn of the year with knock-on effects for the price of rice flour - a key ingredient in gluten-free bread and cakes. Rice flour prices now stand at around £750 a tonne.

At West Lothian-based United Central Bakeries (UCB), which supplies the major multiples with own-label gluten-free bread, sales and marketing director Paddy Cronin said the company had taken a significant hit in the past six months because of rising rice flour costs. "We’re finding it difficult to get hold of stocks because rice-producing countries are limiting exports," he said. UCB introduced a 5 % price rise at the end of last year, and is likely to implement a similar increase soon, he added.

At rice flour miller Doves Farm, MD Michael Marriage said he was paying 60% more for rice compared to end of last year, and would shortly have to implement a 20% increase in the price of gluten-free flours.

Alex Waugh, director of the Rice Association, said that prices have risen because of increased global demand prompted by growing populations in rice-producing countries and increases in the price of other grains. Drought and a switch away from rice growing to biofuel production in the US are also contributing factors. India and Vietnam have imposed export bans to stabilise prices at home.

"The increase in rice prices has been a bigger shock than in wheat because it has moved so fast," said Waugh.