Private label brands - -also known as "store brand" and "own label" -- are produced by manufacturers under contract to a retailer.
The market in the EU has been growing at the expense of manufacturers' own brands, from which they typically make higher margins.
Private label products have the highest penetration in the UK market, compared to the other 15 EU member countries surveyed by Nielsen.
Private label products, including food and drinks, accounted for 40 per cent of the UK retail market in 2006, compared to 38 per cent the year before.
In Germany, all private label products accounted for 30 per cent of sales by value, in Belgium 29 per cent, in Spain 26 per cent, and France 25 per cent.
The Nielsen survey, compiled for the Private Label Market Association (PLMA), examined 16 EU countries, plus Switzerland and Norway.
Private label products accounted for 46 per cent share of the market in Switzerland, where they had the highest penetration of the countries Nielsen surveyed.
While Nielsen had a separate category for bakery products in the UK survey, it is difficult if not impossible to make comparisons in the segment for other countries based on the format provided by the analyst.
BakeryandSnacks.com asked Nielsen to provide an explanation to the confusing method of categorising bakery and snack products for other countries.
Jean-Jacques Vandenheede, a Nielsen analyst, said the firm's researchers are "working towards a common set of definitions but these are not available yet".
However, the UK market serves as the bellwether of the trends underway throughout the EU.
In the UK, the private label bakery segment is among the top five strongest product categories.
UK private label bakery products suffered a 1.3 percentage point decline from 59.6 per cent in 2005.
The decline hides the gains made in certain product sub-categories.
The market for pretzels/salt sticks showed the greatest market gain within the biscuits segment, gaining 10.4 percentage points between 2005 and 2006 to 45.9 per cent.
This was closely followed by boudoir/sponge fingers which went up 7.5 percentage points to 87.4 per cent.
Within the overall bakery segment for the UK, the largest market gain was seen in large fruit pies, gaining 15.4 percentage points to 72.4 per cent.
However, private label packaged sundaes gained 8.5 percentage points to hold 100 per cent of the market.
In France, own branded biscuits are among the top ten product departments, holding 27.3 per cent of the overall market.
Vienna bread and buns gained 5.5 percentage points to hold 32.7 per cent of the market, while snacks in general dropped 5.5 percentage points to 31.6 per cent of the market.
Private label flour confectionery dropped 19.3 percentage points to hold 33 per cent of the market.
In the German own brand market, baking products hold a 60 per cent share, up 2.2 percentage points on 2005.
Own brand hearty snacks were among the top products in the country for market share growth, up 16.4 percentage points to 38.5 per cent of the market.
Private label butter baguettes gained 9.7 percentage points reaching 62.3 per cent of the German market, and fresh pastry gained 4.9 percentage points to hold 50.3 per cent.
In Belgium, however, own brand biscuits and bakery products were among the strongest in the market segments, holding a 32.5 per cent share.
The market for own branded biscuit selections for children was the top gainer in the country gaining 19.1 percentage points to hold 36.6 per cent by value of the market, followed by chocolate biscuits for children gaining 14.6 percentage points to 27.7 per cent.
Own brand exotic mix held the greatest market share of 86.5 percent, followed by trail mix at 72 per cent.
In Spain, private label bakery and biscuits held 22.4 per cent of the overall market, up 2.3 percentage points on 2005.
Own brand cakes held a 50.7 per cent share and own brand bread rolls went up 4.5 percentage points to capture a 38.9 per cent share of the market.
In Switzerland, where private label holds the greatest market share, own branded biscuits hold 59.3 percent of the market, nuts hold a 68.6 percent market share and snacks at 45.7 per cent.
Overall, the Nielsen survey indicates that the private brand market grew in 15 of the 18 countries.
Western European countries had significant growth, despite strong competition from manufacturer brands.
However, the biggest gains were made in Central and Eastern Europe, where modern retailing is rapidly taking root, Nielsen stated.
"For the past few years, the A-brands launched a strong counter attack to stop the expansion made by retailer and wholesaler brands," said Brian Sharoff, PLMA's president.