A woman who discovered a caterpillar in her salad had the same meal returned, minus the bug.

More than half of a group of birthday diners were struck down with symptoms of norovirus, after eating a buffet meal on August 14 last year. The restaurant involved was required to close for cleaning.

A man ate half his steak-and-mushroom pie before finding it was filled with mould. He returned the pie and was given a refund. A warning letter was sent to the owner.

Those are some of the findings from a review of food poisoning incidents by the New Zealand Herald based on papers released by the Ministry of Agriculture and Forestry papers under the Official Information Act.

The papers also reveal some scary behind-the-scenes behavior at restaurants.

Investigations in the wake of complaints show basic hygiene and food-safety practices were not carried out at some outlets:

At one, staff did not wash their hands before preparing seafood.

A food handler worked with an open wound on his arm.

At a kebab shop, investigators found cooked meat was shaved directly on to the drip tray and the same utensils were used for different meats.

MAF spokesman Geoff Allen said he did not see trends developing but he said careful preparation was needed at home and people should choose restaurants carefully.