It's a glimpse at the ratings the government didn't want you to see.

Consumer group Choice has used a new healthy food star rating system - controversially pulled from a federal website by Assistant Health Minister Fiona Nash - to uncover surprisingly large differences in the nutritional content of seemingly similar snack foods.

Choice campaigns manager Angela Cartwright said consumers would be shocked by the results, with a full 2½ stars out of five difference between similar products.

"It often comes down to whether they are cutting corners and using more saturated fat and sodium," she said. "These are products that kids are eating in playgrounds around Australia every day, and people have a right to know."

Choice compared three products from multinational snack foods company Mondelez with similar products, after it called the system "ill-founded, unscientific and confusing".

Choice found Mondelez's Kraft Strip Cheese received only two out of five stars, compared to Bega's Stringers, which got 4½ stars. Mondelez's Ritz Crackers got half a star, compared to Arnott's Jatz Original, which got two.

Mondelez has been drawn into the controversy surrounding Senator Nash's closure of the food star rating website, after it was revealed her chief of staff was involved and was also a co-owner of a lobbying firm that worked for the brand.

Ms Cartwright said Choice wanted to see what impact the ratings would have on companies that had criticised the ratings.

"The health stars shot down the Mondelez product each time,'' she said.

Ms Cartwright said she was able to use publicly available information to do the ratings, and would consider doing more product analysis if the website was not put back up.

Senator Nash has said she intervened in the state and territory controlled website because it would be confusing for consumers when the stars were still being introduced. But she said she still planned for the system to begin in the middle of the year.

A spokeswoman for Mondelez International said the system would mislead consumers and make labels more confusing.

''Given the health star rating shows that Philadelphia Cream Cheese is healthier than an apple, we believe that more work needs to be done,'' the spokeswoman said. ''The 100gram serving size adds another level of complexity. Even the most fervent Vegemite consumer would only use 10 grams.''

She said the Choice review unfairly compared Sanitarium peanut butter with no added salt and sugar to the normal Kraft peanut butter, when it should have been compared to Kraft with no added sugar or salt.

''The algorithm which determines the number of stars on a product has changed numerous times and is expected to change again, so the results of this Choice test should be used with caution,'' the spokeswoman said.