A multi-million pound investment programme has transformed the fortunes of a north Norfolk food factory with a history stretching back more than 60 years.

The Heinz unit at Westwick near North Walsham, built in 1948, now produces most of Heinz's Aunt Bessie range of potato products from chips to wedges.

Heinz has invested more than �16m into the factory in the past four years to boost productivity and efficiency savings in energy and raw materials. But the food giant took a long look at Westwick before backing the 'Operation Trafalgar' strategy, which has transformed the business in the past two years at a cost of �8.4m.

Production services manager Ian Rainford said: 'It has involved creation of one new process line and two new packing lines,' said who is responsible for logistics involving movement of potatoes, packaging, ingredients and distribution of products.

'In the summer shut-down, we made some significant investment again in the new packing lines and new blancher for the older process line and new cutting equipment to enable us to better utilise the potato to make roasts and chips.

'Last year, there was significant investment in odour reduction and noise abatement,' he added.

'We make most of the Aunt Bessie's range of roast potatoes, chips, crinkle cut chips, chunky croquettes and jacket wedges. We don't make bubble and squeak or mashed potato.

'And we've just launched Mid-Week Mini Roasts, which is a smaller version of a roast potato. It is an alternative to chips for a mid-week occasion because it cooks in 20 minutes – instead of roasts which take about 30 to 35 minutes to cook.

'I think they're really good,' said Mr Rainford, who used to work for Birds Eye at Lowestoft handling about 50,000 tonnes of peas.

While total sales have increased, product mix has altered. 'We used to be a roast potato factory which occasional made chips. We're moving to a chip factory which makes roasts. Chips are increasing while roasts are static,' he said. Broadly roasts account for 43pc and chips 52pc.

'My tip for the top is Aunt Bessie's Mid-Week Mini Roasties. We think they will appeal to mums and families,' he added.

'Heinz does all the new product development for Aunt Bessie's. We have a very close relationship to ensure that we're going in the right direction for the brand and to make sure that the products are spot on.

The range includes potato cakes, croquettes, mash potatoes, crinkle cut chips, wedges, baby roasts, flavoured mash, crinkle cut, rustic chips, roast veg and more.

The factory, which covers 11.25 acres, has three main processing lines – one for roasts, one for chips and the third for croquettes. And there is flexibility because the chip and roast lines are inter-changeable.

There are 204 full-time posts and the factory runs 12 hour shifts, with staff working typically four days on, four days off and then four nights but shifts are shuffled to avoid weekend breaks. With an attendance rating of more than 98pc, it is one of the top Heinz factories.

'We tend to have a three-week shut down over summer to allow some of the larger projects to be installed. It also avoids the last few weeks of old crop potatoes which have been in store longer.'

Two or three day maintenance and cleaning shut downs every 20 days allow engineers to do larger projects.

But the key to success is turning as much as possible into quality product. 'If we get better raw material at the back door, we can make better finished products to go out the front door and we're throwing away less in the middle. So it is very much a collaborative effort,' he said.

Factory history

1948 – Factory opened by Alexander and J Carl Ross.

1949 – First pea harvest, produced 13 tons.

1954 – Acquired by Ross Foods.

1968 – First chip line launched.

1999 – Site acquired by UB Frozen and Chilled Foods.

1999 – Aunt Bessie's Roast Potatoes launched

2000 – Growth in the potato market, acquired by HJ Heinz.

2000 - Strategic review started, completed 2005.

2007 - Project Trafalgar

2009 – Investment in noise and odour abatements.

2010 - New equipment in packing and cutting.