Another food-related one would be the exclamation ¡Ostras! (Oysters!) as a polite alternative to ¡Hostia!, as in Gosh! instead of God! The funny thing is that 'hostia', which simply means the 'host', the wafer used in the Eucharist, is not something you would think required a euphemistic variant, but in devoutly Catholic Spain (much less so these days, but...), the idea of using the sacred host as a curse was so shocking that it had to be substituted for the vaguely similar-sounding word for oysters.