The high price of butter means bakers are turning to margarine - or a mix of the two.

There's been panic buying at supermarkets in France as people struggle to cope with a global butter shortage.

New Zealand Baking Industry Association President Kevin Gilbert told NZ Herald Focus bakers are resorting to alternatives to butter.

"So they're either maybe doing a half-half mix with butter and margarine just to maintain as best they can the butter flavour while reducing the price."

However, for one Auckland cafe owner, that's not an option.

Little and Friday owner Kim Evans said sales of donuts have dropped at her two cafes since she put the price up in June due to the cost of butter.

"There's no alternative, for the products that I'm making, for butter. I couldn't use margarine, no way."

Evans said it's quite stressful trying to make her business financially viable.

Gilbert said some bakers are also looking at alternative products that require less butter.