Green’s Dictionary of Slang

yoghurt n.

In phrases

cough one’s filthy yoghurt (v.) (also shoot filthy yoghurt)

to ejaculate.

[UK]Roger’s Profanisaurus 3 in Viz 98 Oct. 9: cough your filthy yoghurt v. A romantic expression for ejaculation. A money shot (qv). ‘Ursula was powerless to resist. His eyes burned into hers like sapphires. His strong arms enfolded her tender body as she felt herself being swept away in a whirlwind of passion. Then he dropped his trollies and coughed his filthy yoghurt’. (from ‘The Gentleman and the Lady’, by Catherine Cookson).
[UK]P. Meditzy ‘A Day In The Life Of...’ 29 Apr. [Internet] It was therefore time for my ‘womb broom’ to experience a bit of action to give ‘kojak’s money box’ a chance to ‘shoot some filthy yoghurt’ into some woman’s ‘furry letter box.’.
[UK]Metro 22 May 37/2: Shouldn’t we be celebrating the schmuck? Bigging up the bald-headed mouse? Euologising the yoghurt-spitting sausage?