Possible Clues:

• Get away from the North so as to get a rise (6)
• Something like yeast
• Help rise
• If one were to desert the North, that would cause a rising
• With this arise and go now-to the North
• Quit the North because of the rising it causes
• Fermenting agent
• So to emigrate from the North gives one a rise
• Substance for producing fermentation
• Substance to make dough rise