(TheAge) - A parliamentary committee has called for an investigation into whether supermarkets Coles and Woolworths are lining their shelves with private-label wines, squeezing out traditional winemakers.

Last week a report from the House agriculture committee raised concerns about the dominance of private-label wines and the impact on competition.

Chaired by Tasmanian MP Dick Adams, the committee pointed to the topic as part of a wider inquiry into the operations of industry body Wine Australia.

Wine Australia chief operating officer Andreas Clark told the committee: ''I think the producer would argue that it is a challenging market for them … trying to get their product into the market with heavy dominance by the two major retailers, and their preparedness to invest heavily in their own brands, which compete on the shelves with the traditional brands, as we call them.''

''So, the producers will say they are getting squeezed, and then that follows down the chain.''

Private-label wines have been a bugbear for the wine industry. Many wines sourced by Coles or Woolworths receive pride of place on their shelves. To consumers they look like traditional brands and some have scored wine awards.

Last year, Ross Brown, the former boss of Brown Brothers winery, criticised Coles and Woolworths for flooding stores with private-label wines that he said were ''hollow'', ''copycats'' and ''masquerading as real brands''.