It is no surprise, then, that the sugar-beet industry was well guarded by Europe’s Common Agricultural Policy. But in recent years the EU has reformed its system of quotas and subsidies to lower food prices and enhance its farmers’ competitiveness; production quotas for milk were dismantled in 2015, for example. Now it is sugar’s turn. From October this year, the EU will abolish its minimum price and production quota for beet. Its complex restrictions on sugar imports will remain, however, as will its income support for farmers.

The beet sector has already been restructured in preparation for the change. EU compensation schemes have facilitated the closure of factories and a decline in the number of beet growers who were propped up by state support. Thanks to improved seeding technology, beet yields have been rising, says Kona Haque from ED&F Man, a commodities-trading house. This is particularly true of producers in the “beet belt”, which runs through parts of Britain, France and Germany. Based on farmers’ sowing this spring, Ms Haque expects production to rise by over 17%, barring unfavourable weather.

The abolition of support for beet also means that the EU will become a net exporter of sugar for the first time in over ten years. (Once processed, sugar from beet is indistinguishable from white cane sugar.) A cap on exports has been in place since 2005, when the WTO ruled in favour of a complaint from Brazil, Australia and Thailand that EU support gave its exports an unfair advantage. Refined white-sugar exports could nearly double to 2.6m tonnes a year once support is removed, says Claudiu Covrig from S&P Global Platts, a provider of commodity-market information. But they are unlikely to return soon to the peak of 7m tonnes seen before the WTO ruling: that would require significant investment in export infrastructure. European exporters will face more competition, too: former customers, such as those in the Middle East and northern Africa, set up their own cane-sugar refineries once EU exports dried up.

How much production and exports increase will depend on world prices. As the beet industry restructured, the EU sugar price fell significantly, from more than €700 ($742) a tonne in 2013 to around €500 in early 2017, close to the world sugar price. As the sector becomes less protected, it seems likely that European prices will move more closely in line with the volatile world sugar price. That could affect farmers’ decisions to grow beet. They would remain competitive at modestly lower prices, but sharp price falls would deter them from sowing beet altogether. Processing plants are offering farming co-operatives long-term contracts to stabilise supply, and financial-market forward contracts offer the industry a way to hedge against price movements. But no one knows how effective these contracts will be.

The changes do not mean, though, that cane and beet are on an even footing in Europe, says Gerald Mason at Tate & Lyle Sugars. Cane continues to be hamstrung by import restrictions. A system of tariffs and quotas makes trade with the most efficient low-cost producers, such as Brazil and Mexico, prohibitively expensive.

African, Caribbean and Pacific cane producers will continue to receive preferential access to the European market. But many are inefficient, high-cost producers and are uncompetitive now that European sugar prices have fallen. The solution is for them to diversify (the EU has made funds available for this purpose). Some countries will cope better than others. Mauritius and Belize, for example, are using cane to produce speciality sugars, ethanol and electricity; African producers, such as Zambia and Malawi, could export to regional markets. But, according to a July 2016 report for the European Commission, Caribbean producers such as Guyana and Jamaica have diversified little so far. With exports to Europe expected to fall drastically, their rural unemployment rates will probably spike.

The EU’s cane refiners—which, according to the European Commission, are based in nine member states—will find their margins squeezed as white-sugar prices fall but imported raw-sugar costs stay high. Tate & Lyle Sugars ran a €25m loss in the year to September 2015, for which it blames import restrictions. This is why the company came out in favour of a British departure from the EU: Mr Mason views Brexit as a “golden opportunity” to establish rules that treat cane and beet as equals in the British market. Beet producers have a different notion of fairness: for them, a level playing-field is one that takes into account the state support other producers receive. Precisely how the British government will keep both sides sweet is anyone’s guess.