The Highland Toffee bar could vanish from shop shelves after its makers went into receivership.
Jobs at Stenhousemuir and Broxburn are set to go within weeks
Millar McCowan, which also produces Wham bars and Pan Drops, is set to shut with the loss of 149 jobs.
The close of the business marks the end of a Scottish sweet-making tradition that began in 1884.
Jobs will be lost within weeks at the confectioner's plants in Stenhousemuir, near Falkirk, and Broxburn, West Lothian, unless a buyer can be found.
The firm had struggled with restructuring costs since being formed from the ailing John Millar and Sons and McCowan's last year.
Graham Wallace, chief executive of Millar McCowan, said: "I am very disappointed that we have not been able to keep both sites running and I am particularly sorry for the loyal employees who have faced a lot of anxious moments over the last two years.
"This is a difficult and competitive sector of the UK confectionery market and so, unfortunately, we cannot keep something running that is not working commercially."
McCowan's was established in Stenhousemuir in 1922
John Millar and Sons was founded in 1884 in Edinburgh
Millar McCowan was established last year in an atempt to save the firms
The company sells more than 140 million chew bars a year
Highland Toffee is exported around the world
The firm also makes Irn-Bru bars and Desperate Dan bars
Mr Wallace and business partner Andy Allan bought the struggling sweet companies when they went into receivership in the middle of 2005.
United under the name Millar McCowan, the business attempted to re-establish its top brands.
Graham Martin of administrators PricewaterhouseCoopers said: "The costs of internal restructuring and the time taken to re-establish the brands in their chosen markets have led to cash and creditor pressures.
"It is with regret that the decision has had to be taken to close manufacturing at both sites with the loss of 149 jobs.
"Eight staff are being retained in the short term."
John Millar and Sons, producer of pan drops and chocolate eclairs, was founded in 1884 by the Edinburgh baker.
McCowan's was established in 1922 by Andrew McCowan and manufactured its flagship brand Highland Toffee, one of Scotland's best loved sweets, for more than 80 years.
The chew bar Wham, a fizzy fruity bar topped with sugar, was introduced in the 1980s and sold more than 30 million bars a year.