The pie’s lid usually rises in the oven, creating a space between the fruity mixture and pastry, which can cause the pie to sink when it’s bitten into and leave customers deflated.
But now Asda’s Innovation Chef Mark Richmond and his team have come up with a solution - and taste-tested more than 750 pies in the process - to close the gap in time for Christmas.
The production line is using a new crimper which compresses the pie as it attaches the lid - thus eliminating the air which normally expands during baking.
And this hypnotic video shows the improved mince pies rolling off the production line at the Asda mince pie HQ in Barnsley, South Yorks, at the rate of 720 every MINUTE.
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Mark, 42, from Ripon, North Yorks, said: “I’ve wanted to reduce the common mince pie air gap for years and this year we finally have.
“We’ve filled the pie with as much mincemeat as possible and used some clever technology to press the lid onto the pie which removes all the air - just like I would when making pies by hand with my granny when I was young.
“It was simply a case of reverting back to my grandma’s kitchen and how she used to close that gap.”
The mesmerising video follows the process from start to finish as buttered pastry is piped down from a secret room onto the production line.
Asda’s secret recipe of pre-mixed ingredients including fruit and spices are then pumped into each base before being sealed with pastry lids.
Quality control teams patrol either side of the line to ensure no glitches occur before the pies are ushered into a huge oven for nine and a half minutes.
Mark said: “The line creates 720 mince pies a minute so we’ve got to get it right. I think even Willy Wonka would be happy with this process.
“A mince pie is a real Christmas tradition and it was very satisfying to draw on my grandmother’s system to produce a pie that is filled without a gap.
“The video is oddly hypnotic to watch.”