Image copyright United Biscuits

The number of Jaffa Cakes has been cut from 12 to 10 in the latest example of packaged food "shrinkflation".

The packs weigh 122 grams rather than 150 grams, but McVitie's has cut the recommended price from £1.15 to 99p.

Twin packs, which now have 20 cakes rather than 24, are now £1.89 rather than £2.19.

"These changes represent the same price per cake, however, pricing ultimately remains at the sole discretion of retailers," the firm said.

Tesco and Sainsbury were both selling a box of 10 for £1.

On online provider Ocado, the boxes were priced at £1.19.

A McVitie's spokesman added: "There is no change in the size, shape or weight of individual cakes in the McVitie's Jaffa Cake range."

That, of course, did not stop aficionados taking to Twitter to express their feelings about the "Jaffa quake".

However, others welcomed the move:

Earlier this year McVitie's reduced the size of its dark chocolate digestive biscuits from 332g to 300g - a 10% reduction.

It is far from the only company cutting the size of its products rather than raise prices following increases in costs.

In July, the Office for National Statistics said as many as 2,529 products had shrunk in size over the past five years, but were being sold for the same price.

As well as confectionery, these included toothpaste, orange juice and toilet roll.

Jaffa cakes were first produced by McVitie's in 1927.

Contrary to popular belief, the main flavouring in the jam insert is apricot, with an added note of tangerine oil, although they are named after the Jaffa orange.

The company was challenged by Her Majesty's Customs and Excise that a Jaffa cake was a biscuit and therefore subject to VAT.

McVitie's says on its website that it "successfully proved to the courts that a Jaffa cake is indeed a cake, and it is still VAT free to this day".