Breakfast cereal. Frozen foods. Herbs and spices.

When the cost to make those things goes up, you're probably going to end up paying more for them at the grocery store. So get ready, because global food commodity prices climbed again in September.

Already, some major food makers are raising prices, and others are talking openly about going down that road.

The United Nations Food and Agriculture Organization's Food Price Index, which tracks international commodity or export prices for cereals, vegetable oils, dairy, meat, and sugar, averaged 136 points in September, up 1.5% from a revised 134 points in August and 5.8% from a year earlier.

After declining in May and June, the index has risen for three straight months. It has reached the highest level since November 2022, though it's still 15.1% below its March 2022 peak.

In September, the biggest moves came from sugar and grains. The FAO Sugar Price Index jumped 6.1% from August as lower production expectations in Thailand, below-normal rainfall in India, heavy rains in Brazil, and reduced European Union sugar-beet acreage raised expectations of tighter global sugar supplies.

The cereal index rose 5.1%. Wheat prices climbed 6.3% as Black Sea shipping constraints and dry North American weather raised supply concerns, while maize gained 5.6% on weaker U.S. yield prospects, reduced Brazilian export availability, and trade disruptions. Vegetable oils rose 0.9%, while meat fell 1.1% and dairy slipped 0.1%.

This doesn't mean U.S. grocery prices will immediately rise by the same amount. Retail food prices are affected by many costs beyond raw commodities, including labor, processing, packaging, transportation, energy, and wholesale and retail markups.

Still, sustained increases in costs can eventually squeeze manufacturers. If productivity boost and other offsets fall short, companies may ultimately have to absorb more of the costs in their margins or pass them on to consumers through higher prices, potentially hurting volumes.

General Mills said last week that fiscal-2027 input-cost inflation is tracking toward the high end of its previously expected range of 4% to 5%. The company expects to generate at least $750 million in cost savings this fiscal year. Management said it might also resort to price increases and other tools to offset higher costs.

Likewise, Conagra Brands said this week that inflation should land near the high end of its 5% to 6% range, noting that transportation inflation has doubled from its initial plan due to driver shortage and high oil prices. The company has already begun rolling out price increases, and expects to generate productivity savings of more than 4% of cost of goods sold for the year.

McCormick on Thursday raised its full-year cost-inflation expectation to 6% to 7%, citing rising commodity and freight costs. The company said pricing and productivity savings helped offset inflation in its third quarter, but the pressures are expected to intensify in the fourth quarter, which could contribute to a year-over-year decline in gross margin.

Shares of General Mills, Conagra, and McCormick have fallen roughly 31%, 23%, and 34%, respectively, this year through Friday's close.

For food companies, the next test will be whether productivity savings can keep pace with inflation. Otherwise, companies may have to lean more heavily on price hikes.

If commodity inflation persists, pricing power could once again become a key dividing line.