[ray gower]

Short answer:
Provided it is in context, a short outburst signifying something is not as it ought to be, then don't change that one word. Even my dear old white haired mother will have no problem.

Longer thought:
When swearing under stress, it is not the word that matters, it is the effort expended saying it. You can put as much meaning and satisfaction in an inappropriately exploded "Sugar!" as any expletive. So it just needs to be something that can trip off the tongue in a sudden outburst.