Global grain markets possess the "recipe for strong volatility" despite apparently strong inventories, AHDB lead analyst Jack Watts said – likening dynamics to those in banking markets ahead of the world economic crisis.
"Complacency over supply, we see have seen that time and time again," Mr Watts said, noting that the world in 2017-18 looked like seeing a fifth year of grain production surplus.
However, flagging supply risks, particularly in wheat, he said adding that "the recipe is there for strong volatility" in prices.
"All looks calm on the surface, but there are key risks to be aware of."
One was the growing proportion of wheat inventories held in China, and so effectively unavailable to the world market, a factor which was "distorting perspectives" on global supplies.
"There is real divergence between global wheat stocks and accessible wheat stocks," he told the AHDB grains outlook conference, with world wheat inventories outside China at their tightest in nine years, when compared with demand to form the stocks-to-use ratio, a much watched pricing metric.
And the growing reliance too on Russian wheat supplies was also a factor for concern, given the country's record of occasional heat-devastated harvests.
"The market is growing in confidence in the consistency of supplies coming from Russia," expected to become the world's top wheat exporter in 2017-18.
However, if the world were to see a repeat of hiccups which beset crops in the likes of 2010 and 2012 "the impact would be much bigger because Russia has a bigger role in supplying wheat to the world."
The trend towards "deglobalisation" evident in growing nationalism in many countries also represented a potential cause for concern, given that 25% of world wheat output is traded.
"Any threat to globalisation would have quite a big impact on the ability of the wheat market to function," he told the conference, in London.
There were "passive risks beneath the surface for grain markets" which were "not dissimilar to passive risks building up 10 years ago" in the banking sector ahead of the global economic crisis.
"Long-run risks to the global grain market are growing," Mr Watts said.
By Mike Verdin