A morals versus money battle ended a quantum physicist’s run on The Apprentice last night.

Sir Alan Sugar fired Dr Sophie Kain, 32, after she complained in the boardroom that she did not want to sell something that she did not believe to be “value for money”.

Sir Alan, whose personal wealth is estimated at £780 million, was not impressed by Dr Kain’s stand against selling lollipops to children at London Zoo.

“This is the real world love, this is not your scientific protons and neutrons. That’s what retailers do. It’s the pot calling the kettle black.

"The pharmaceutical industry are the biggest culprits going. These pills that we're popping all the time curing diseases, cost fractions of pennies to produce and then the National Health Service is laying out £500 a pill.

"I'm wondering, have I got another one here who should really stick to what they know? ... You're fired!"

Dr Kain, who has a PHD in Theoretical Physics, said she didn’t regret speaking her mind about peddling sweets to children.

"I've learnt from the programme that I value my principles more than money.

"I'm never going to be rich but I am going to be successful."

"I didn't believe in pushing lollipops to kids. I thought what we were asked to do was a little bit intimidating."

Dr Kain will return to her former job as a principal research scientist and is also planning to set up an internet advisory service.

The fifth contestant to be fired, Dr Kain leaves 11 contestants behind competing for a six-figure salaried job with Sir Alan.

Editor's choice

• The 100 Best Films of the Decade
• 70 facts you didn't know about Marvel
• The 50 Biggest Movies Of 2010