A needle was reportedly found in a grape bought from a Victorian Aldi store and police are investigating, weeks after reports of spikes in strawberries.

Chloe Shaw posted to Facebook on Sunday that she had made the discovery and contacted the retailer and police.

"Grapes I purchased today from ALDI Caroline Springs. Please check all your grapes before eating especially if your giving them to your kids," she posted alongside two photos of a halved green grape with a metal spike inside.

Victoria Police confirmed an investigation is underway.

"The community is reminded that anyone found to be contaminating food products can be charged with a serious indictable offence with penalties including up to 10 years in jail," the force said in a statement.

Aldi issued a one-line statement on Monday: "Food tampering, involving the deliberate interference with food is a criminal offence and we work with authorities on all reported incidents."

The grape tampering comes two weeks after police confirmed they were investigating needles found in strawberries.

A needle was found in a strawberry bought at a Fairfield store on August 25 and reported to police on September 10.

Another strawberry bought at Eltham on September 23 had a metal spike and was reported to police the next day.

Last year Australian strawberry growers were rocked as police across the country investigated more than 100 reports of fruit being contaminated with needles and other objects.

Many of the reports were found to be fake or copycat incidents but the scare prompted the federal government to rush through tougher penalties for so-called "food terrorists".