They are given to provide a clear indication to customers about the standards of a takeaway, restaurant or other food business.
Inspections are carried out by local authorities throughout the year.
Businesses are given a rating from zero to five, with zero being the lowest.
Portsmouth City Council carry out the inspections in the city.
Environmental health officers review the state of hygienic food handling, management of food safety, and the cleanliness and condition of the facilities and building at each location.
MORE LIKE THIS: 9 latest food hygiene ratings for restaurants, takeaways, cafes and pubs in Portsmouth
These are the four businesses that currently have a zero food hygiene rating in Portsmouth.
You can see the full list by clicking through all the gallery pages.
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1. Florio's D'Italia, Claybank Road, Copnor
Italian deli Florio's D'Italia received a zero rating on April 23, 2021. The Food Standards Agency website said the hygienic food handling standards are good but improvement was necessary for cleanliness and condition of the facilities and building, and urgent improvement was needed for management of food safety. Photo: Picture: Habibur Rahman
2. Golden Chopsticks, North End
Golden Chopsticks received a zero food hygiene rating on July 14, 2021, according to the Food Standards Agency website. The FSA said major improvement was necessary for hygienic food handling, the cleanliness and condition of the facilities and building and management of food safety. Photo: Google
3. Star of Asia, Marketway
Star of Asia received a zero food hygiene rating on September 21, 2021, according to the Food Standards Agency website. The FSA said urgent improvement was necessary for management of food safety. Major improvement was necessary for hygienic food handling and the cleanliness and condition of the facilities and building. Photo: Picture: Google Street View
4. Tasty On The Go, Fratton
The takeaway Tasty On The Go, based in the Bridge Shopping Centre in Fratton, received a zero rating on October 21, 2021, according to the Food Standards Agency website. The FSA said urgent improvement was necessary for management of food safety, and the cleanliness and condition of facilities and the building. Major improvement was necessary for hygienic food handling. Photo: Other