A Dunedin man with a hankering for pineapple juice allegedly pulled a knife on a bartender when he could not get his tropical fix.

The 54-year-old man was at Vault 21 in the Octagon on Saturday when he went up to the bar to ask for a glass of pineapple juice, Senior Sergeant Iain Notman said.

Unfortunately, Vault 21 did not have any. 

This made the man irate and he allegedly pushed a server down then pulled out a butterfly knife — an illegal folding pocketknife similar to a switchblade. 

He then brandished the knife at the server, Snr Sgt Notman said. 

Police were quickly flagged down and arrested the man immediately. 

Snr Sgt Notman said he was charged with behaving threateningly and unlawful possession of a knife.

He would appear in Dunedin District Court at a later date. 

laine.priestley@odt.co.nz