Raymond Hodgson, 31, from Carlisle, Cumbria, pleaded guilty to the single charge of common assault.
Prosecutor Adrienne Harris said that Hodgson and girlfriend of five years Emma McCormick began arguing on June 25, after McCormick began reading the notorious book.
She went on: “Mr Hodgson thought that the book was pornographic, and that she should not read such literature.
“The argument continued into the following day, with the two exchanging text messages.”
Harris continued: “He went to her home at 7pm on June 26 and took with him a bottle of brown sauce.
“She answered the door and the argument continued.
“She went to close the door and he jammed his foot into the door, slapped her once in the face, and then squirted her with this bottle of sauce.”
The court also heard that, following the incident, Hodgson had told police that 50 Shades of Grey was “distasteful” and “pornographic”.
Hodgson denies slapping McCormick and said he was “sorry” for squirting the sauce.
Harris said: “He didn’t realise that the sauce incident would be classed as an assault. He is sorry for his actions.”
District Judge Gerald Chalk ordered Hodgson to pay £100 compensation and £85 towards prosecution costs.
After the case, Hodgson reportedly said that he chose his weapon in order to show McCormick “what sauce really meant”.
