The Aunt Bessie’s frozen Yorkshire puddings and roast potatoes business has been sold for €240m (£210m) to a US-listed investment business founded three years ago by a billionaire former hedge fund manager and an ex-investment banker.

Nomad Foods, which is listed on the New York Stock Exchange, is buying Aunt Bessie’s from William Jackson Food Group, a 167-year-old family firm based in Yorkshire.

The deal includes a factory in Hull and will bring together Aunt Bessie’s – the UK’s number one brand for frozen Yorkshire puddings – with Nomad’s other investments, which include Findus, Birds Eye and Goodfellas Pizzas.

Aunt Bessie’s – which last year made £20m profit from revenues of £108m – employs 400 people, all based in Hull. Nomad said all staff would transfer to Birds Eye when the deal is completed in the autumn, taking the group’s total workforce to 1,600.

Nomad was set up four years ago by the billionaire Noam Gottesman, the co-founder of the GLG hedge fund, and the British-born financier Martin E Franklin, as an investment vehicle in London. It later switched its listing to New York.

William Jackson is a sixth generation family firm based in Hessle, near Hull, which also owns the organic vegetable box business Abel & Cole, Jackson’s Yorkshire Champion Bread brands, a local pub and The Food Doctor healthy snacks.

Wayne Hudson, the Birds Eye managing director, said: “Aunt Bessie’s is an incredibly well-known brand. This is a growth story – we have no intentions to close the plant and are integrating it into the Nomad Birds Eye business.”

Frozen food is growing faster than fresh, chilled and shelf-stable food, thanks to convenience, higher quality and waste reduction, he said. According to Kantar Worldpanel, frozen food sales rose 6.1% last year, with savoury food up 8.8%.

The deal comes only a few weeks after Nomad bought Goodfellas, the UK’s biggest frozen pizza brand, for £200m from the food tycoon Ranjit Boparan. It will help the food company strengthen its position in the UK, which it described as a “strategically important market”.