It wasn't jewellery, a romantic meal for two or even a weekend away that Tim Sander bought his loved one for her 35th birthday.

It was a visit to a crisp factory - because the lady loves... er... Nik Naks.

Primary school teacher Natasha Mills got the shock of her life when her boyfriend indulged her love of snacks and gave her the unusual present of a tour around a Golden Wonder crisp factory in Scunthorpe.

Tim, 40, who has dated Natasha for five years, said: "I guess it is always easier to go for something from the shops but I wanted to do something unusual.

"I thought about all the things she likes and decided to contact a few factories in the area.

"They made us feel so welcome and the personal touch they gave us on the tour was second to none. Furthermore they did not charge us a penny."

Tim, an environmental campaigner for Friends of the Earth, said Natasha had enjoyed a passion for the crisps since they met.

"Her favourite flavour is nice and spicy. She probably has at least a packet a week," he said.

Natasha will be able to eat her fill now as she received free boxes of the snack from the factory.

"She was delighted with the gift," said Tim. "But there are no plans to get married there.

"The only problem is now that I have set myself a high precedent. I do not know if I'll be able to top this next year."

Mark Coome, training co-ordinator at the factory, admitted the request was unusual.

"In the past we have had guys asking if they can come to the factory and propose to their girlfriends but this is one of the more unusual requests we have had," he said.

Not only did the Oxenhope couple get to see the entire process from potato to crisp, Natasha also received a bouquet and a look at the Riley's crisps exhibition at North Lincolnshire Museum.

She said: "This is the most unusual birthday present I have ever had, but I was very excited. Last year Tim bought me some bubble bath."

In every eight-hour shift at the factory, 90 tonnes of potatoes are used to produce 15,000 bags of Nik Naks and every 24 hours two million bags of a variety of crisps are produced.