High Street chain Greggs is to close three of its 12 bakeries in the UK, including one in Scotland.
The closures in Edinburgh, Twickenham in London and Sleaford in Lincolnshire are likely to lead to the loss of 355 jobs.
Greggs is in the process of switching its focus from being a traditional baker to selling more food on the go.
It confirmed it was investing in its Clydesmill bakery in Glasgow to create a "centre of excellence" in Scotland.
The reorganisation of Greggs was announced as the company reported a 25% increase in underlying annual profits to £73m for 2015.
In 2013, Greggs announced a plan to focus on the £6bn food-on-the-go market.
The Newcastle-based company has concentrated on selling sandwiches, sausage rolls and pastries, but it said customers were now buying healthier foods such as salads and soups.
Greggs has about 1,700 shops and said it was confident it could increase the number to 2,000.
As part of a £100m investment over five years, the company said it planned to upgrade its Enfield bakery in London as well as the the bakery in Glasgow.
A spokesman said: "Greggs currently operates from 12 bakeries; unfortunately not all are suitable for long-term investment due to their location and size.
"These are difficult changes that we believe are needed to support the long-term growth of the business; however our immediate priority is to work to minimise the negative impact on our people, many of whom have worked in these roles for a significant number of years.
"Wherever possible we would look to offer alternative employment to affected employees but, due to the location of our sites, we anticipate that unfortunately many will leave the business."
He added: "Our recently-acquired distribution facility in London will enable us to invest in our Enfield bakery to create a manufacturing centre of excellence in the south east region and we now propose to invest in the extension of our Clydesmill bakery in Glasgow to create a centre of excellence in Scotland."
Last year, leading Scottish politicians including Nicola Sturgeon and Kezia Dugdale backed a Scotland-wide campaign for Greggs to "save the macaroni pie" after the savoury treats were axed.