Possible Clues:

• Source of zest
• Fruit's outside, awfully large one: half of pear inside
• Curaçao ingredient
• Ape English PM going round Jaffa?
• Citrus fruit waste
• Rind often candied
• Bar garnish
• Part of fruit left after ape offered blade?
• Candied item
• Pithy stuff from Dutch house hunter