Possible Clues:

• An apple may be firm and brightly coloured
• Took the heart out of
• Readied apples for cooking
• With Conservative taking the lead, old socialist becomes disheartened
• Fellow socialist disheartened
• Prepared apples for baking, e.g.
• Did a strudel-making job
• … like apples baked by fellow revolutionary …
• Removed the middle of, as an apple
• Cut out the middle of