A shop assistant was punched in the face on Saturday as she tried to stop a shoplifter stealing three Peperami sausages.
Jacqueline Winters, 45, of Harrowby Close in Grantham, admitted assault by beating and shop theft.
The court heard how Winters walked into the garage in Manthorpe Road and picked up four Peperami sausages, concealing three of them inside her cardigan and paying for the fourth.
Winters was approached by a member of staff who had spotted the theft and did not want her to leave with the items.
Daniel Pietryka, prosecuting, said: “The sales assistant stopped her and challenged her by trying to take hold of her arm which resulted in Miss Winters punching her in the face and pulling her hair.”
Bill Frasier, defending, described Winters actions as “foolish”.
He added: “She apologies through me. She should not have struck the shop assistant who was only trying to do her job.”
Mr Frasier told the court Winters has mental health issues.
The case was adjourned prior to sentencing to tie in with other matters. Winters was released on conditional bail to reappear on June 14.