Aldi has recorded a 450% rise in operating profit to £103m as turnover rose 29% to £2.7bn.

Aldi said organic growth and a £30m store refit led to the uplift in sales in the year to the end of December 2011.

The German discounter returned to the black with a £57.8m post-tax profit compared with a £56m loss earlier in the year, when it was hit by a £58.5m property writedown, according to accounts filed at Companies House.

Aldi also set out its ambitions to increase its store portfolio. The discounter is to invest £181m in opening 40 new stores by the end of 2013 and will open 35 to 40 each year after that.

Its store estate will stand at more than 500 shops by the end of next year and Aldi will employ 4,500 people. The retailer said it could potentially double its UK store base to 1,000 over the next 10 years.

UK joint managing director Roman Heini said: “We still have many white spots on the map, so we still see more opportunities.” However, he added that smaller town centre sites had become a “battleground” between the discounter and its rivals.

Aldi has recorded impressive double-digit growth throughout 2012 and Heini is confident that it has the strongest proposition. He said Aldi is winning customers from “basically all other retailers”.

The grocer’s proposition of discount brands, short-term deals and a small number of upmarket products has appealed to under pressure consumers looking for both value and treats while eating in.

Heini said this combination has allowed a shift in its customer base.

He said: “We’ve seen a shift in the socio-demographics. “Obviously we have kept the existing customers… so we still have the C1, C2 and D customers, but we certainly now also see more A and especially B customers in our existing stores and also in the stores we have opened this year so far.”

Heini added: “We’re tracking similar growth in 2012 in terms of sales volumes and turnover, and store footfall.  Aldi has become more relevant to British consumers. They can buy what they need and want at Aldi, at a price they like. Our customer-focused approach and expansion plans will help sustain our market share and growth in the long-term. People no longer feel they need to shop at Aldi, they want to shop in our stores.”