Food manufacturer Heinz has been fined £20,000 after a worker at its Wigan baked beans factory lost a finger in industrial machinery.
The 65-year-old had an index finger torn off while he was making a new part for a packaging machine, Manchester Minshull Street Crown Court heard.
Heinz admitted two counts of contravening health and safety laws.
The worker was using an emery cloth to polish the component on a rotating machine, when his hand was pulled in.
The victim also suffered nerve damage to two other fingers and cut his hand during the incident at Heinz's Kitt Green plant on Spring Road in April 2008.
The court was told that Heinz should have assessed which safety measures were required before the work was carried out and could have provided an alternative way of polishing the metal part so that an emery cloth did not need to be used.
Health and Safety Executive (HSE) inspector Deborah Walker said: "This worker has suffered severe injuries to his left hand, which will affect him for the rest of his life, because Heinz didn't make sure he was working safely.
"He had been employed by Heinz for more than 20 years, but was not given any refresher training on safe working practices in that time.
"The risk of emery cloth being pulled into rotating metal-working machines is well known.
"Manufacturing companies should make sure employees are following the latest health and safety guidance on this issue."
Heinz, which has its headquarters in Hayes, Middlesex, was also ordered to pay £4,496 in prosecution costs.