Kerman-Shali, of Friern Barnet Road, north London, admitted one charge of theft at Hendon Magistrates' Court on Saturday and was fined £65. He was also ordered to pay a £15 victim surcharge to the store.
A police source said officers were "stunned" to discover the etrog's value after arresting Kerman-Shali, having initially believed he had taken a lemon, worth around 30p.
It is not known whether the etrog was returned to the store before Yom Tov.