The borough was given the accolade last month.
Merton won an award for good food in London in October, yet almost one in five food outlets on Wimbledon Broadway scored a low food hygiene rating.
The Good Food for London award was given to Merton along with Islington, with maps being released of the best areas in London.
Yet seven restaurants and cafes out of 36 on Wimbledon Broadway have a two or less score out of five by the Food Standards Agency.
“In the wake of the ‘horsegate’ scandal, Londoners want to know that their boroughs are serving good food that they can trust,” said Ross Compton, the report’s author.
“The maps paint an inspiring picture of progress by many London boroughs towards better food. The maps also challenge those boroughs that are lagging behind to follow the good example set by Islington and Merton.”
The Good Food league table, now in its third year, compares London’s local authorities on their support for good food initiatives, including improving food served by local food shops.
There are also around 10 zero rated premises out of about 1100 premises in Merton.
“The council ensures that a high standard of food safety is maintained in all food premises in the borough and was one of the first London boroughs to fully implement the national Food Hygiene Rating Scheme,” said a spokesperson for Merton Council.
“Food standards are high in Merton and we do not have a problem with food safety.”
The Food Standards Agency register all food premises within each borough and are visited and rated after an officer has made a planned visit.
The owner is told of their rating immediately after the visit and is given the appropriate certificate and window sticker. Yet there is currently no requirement to display them.
All zero rated premises are inspected at least every 6 months and the officer works out an improvement programme with the owner. If premises do not improve then as a last resort prosecution could occur.
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