Whether it's fried, baked or mashed, potatoes have traditionally been a low-cost staple food in the UK - but not any more.
A surge in costs is clobbering high street chippies, while in the supermarket, oven chips and the once humble baking potato are casualties of soaring grocery prices.
Some fish and chip shops could opt to close after the cost of 25kg sacks more than doubled to £20, said Andrew Crook, who speaks for the industry as the president of the National Federation of Fish Friers.
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"People might just shut their shop due to all the other costs as well," he said. "They were barely keeping their heads above water, so this is going to be a step too far. Some shops will close until potato prices settle down but some it may put under."
While figures this week revealed that the steadying of energy costs after a period of big increases had brought the UK's annual inflation rate back down to 8.7% last month, food and drink prices are still rising at the fastest pace in more than 40 years, up 19% in the 12 months to April.
Chippies buy potatoes in smaller quantities on the open market, so are more exposed to price moves than retailers and food manufacturers who secure long-term contracts.
Even before this new pressure, official data had revealed that the price of a fish supper in the UK had risen to an average of £9 - up £1.44, or almost a fifth, compared with a year earlier - with shop owners hit by rocketing costs for fish, cooking oil and the electricity that powers the fryers.
With rising energy, labour and ingredient costs affecting the whole food industry - and last year's UK potato crop smaller than usual in part because of last summer's drought - a snapshot of supermarket prices reveals the amount they are charging for potatoes and chips, traditionally an affordable and filling accompaniment to any meal, has jumped in one case by almost 60%.
Once a cheap family staple, a four-pack of supermarket own-label baking potatoes now costs 25p more than a year ago at 69p. This works out as a 57% price increase, based on the average price across Tesco, Sainsbury's, Asda and Morrisons, according to the data firm Assosia.
Meanwhile, a bag of 1.2kg-1.5kg supermarket crinkle-cut oven chips is up 78p, or 49%, at £2.35. The sample also showed that the price of a 2.5kg bag of baking potatoes had risen by 28p or 18% to £1.83.
These price rises contributed to the 24.8% increase in potato prices captured by the latest Office for National Statistics data released on Wednesday.
Mark Taylor, the chair of the industry group GB Potatoes, said that in 2022 growers had faced a "perfect storm" as Brexit, Covid and the invasion of Ukraine pushed up production costs. Meanwhile, smaller crop yields in the UK and mainland Europe last year meant "there is a supply and demand equation going on as well".
The UK is "90%-plus self-sufficient" in potatoes, added Taylor, who said that while some farmers grew crops to contract, others sold on the open market. Prices in the latter were not only being influenced by the UK but by "exceptionally strong demand elsewhere in Europe because they are very short of potatoes at the moment".
The UK is very good at growing potatoes, which are still very affordable compared with pasta and rice, Taylor said. Pasta and rice are up by 27.7% and 14.9% respectively over the past 12 months, according to the ONS. "While we've seen an increase in prices on the shelves, we still do believe that potatoes are good value for money," Taylor said.
The price of European processing potatoes, which are used to make many of the french fries eaten in the UK, is up 66% on a year ago at ?420 (£365) a metric tonne, according to Mintec, the commodities data group. English maris piper and packing whites, the varieties found in supermarkets, are up 123% and 284% respectively to £380 and £365 a metric tonne.
"As supplies have decreased over the course of the season, good demand for fresh potatoes and finished products has led to buyers competing for dwindling stocks," the Mintec analyst Harry Campbell said.
"Chipping potatoes are typically not grown on contract which means any rises in free-buy prices are fully reflected in the prices paid by the shops. This has meant that chippies have seen major increases with little to no price stability."
The tightening of UK potato supplies meant chippies may have to source spuds from Cyprus or Spain, although that could mean paying more than £30 a sack, Crook said. "There is a [chip] shop in my town which says closed 'until further notice' on the window. I'm guessing that's because of commodity prices."