Possible Clues:

• Such salt is needed to speed up the work of the Queen of Hearts
• Source scratching head in front of judge in compound
• Baggage charge for a salt?
• At that rate, what's sweet is salt
• Salt for strumpet's roast
• At this rate it's sweet, it seems, as well as salty
• It's sweet - at this rate it's salt
• Set a value on pie first having salt
• What a sweet speed is salt!
• Salt, ie sailor, given special treat