LONDON (AP) -- Is there a doctor of chocolate in the house? Cambridge University in England is seeking a doctoral student to pursue what sounds like the sweetest job in the world: studying the fundamentals of chocolate. The research goal, according to the job description, is to identify ways of keeping chocolate-based food from melting in warm climates. That's a challenge given that even the best-quality chocolate starts going soft around 34 degrees Celsius (93 Fahrenheit), below human body temperature. A solution could fatten the profits of the world's top 10 chocolate companies, which last year posted confectionary sales exceeding $85 billion. Only European Union citizens can apply for the post under the direction of experts in chemical engineering, geotechnical engineering and soft matter physics.