Vanilla production problems may add 20p to cost of a 99
Ice cream prices could go up by 10% this summer because of the soaring cost of vanilla.
It means the cost of a 99 could rise by 20p to around £2.20.
Production problems in Madagascar, the world's largest vanilla producer, have caused prices to surge 120% year-on-year, meaning vanilla beans priced at around £14 per kilogram five years ago are now in excess of £155 per kilogram.
The hike could affect a range of companies including soft drink manufacturers and bakers, but ice cream makers are likely to be harder hit as it is the most expensive ingredient in the production process.
Arnaldo Morelli, boss of the Causeway coast's Morelli Ice Cream chain, said he hoped the family-owned brand would be able to freeze prices.
"Some big name brands such as Haagen-Dazs are very into intense vanilla flavours but our vanilla flavours are more subtle," he added.
"We do put vanilla in, but it complements the other ingredients rather than overpowering them."
Mr Morelli said the firm had not increased prices a couple of years ago after a bad crop and was prepared to do that again in the short-term. "The rising price of vanilla will increase the costs of making our ice cream but we'll bear the immediate increase," he added.
"If this is prolonged we may certainly have to look at it, but hopefully that won't be a concern for ice cream lovers during the summer."
Mr Morelli, who heads up the fourth generation of the family firm which has been producing ice cream here since 1911, said a large 99, which currently costs about £2, could potentially go up to £2.20.
Vanilla is increasingly in demand in foreign markets such as Asia where, according to industry experts, rising personal income means more people are able to spend money on luxuries such as ice cream.
The price of vanilla is likely to stay high for the foreseeable future.
"Madagascar always dictates things," said vanilla pod importer Harry Rao.
"It's not a controlled market because a few big suppliers dictate the market. The cost of vanilla tends to rise quickly but fall very slowly."