These are the 'worst offenders' in Australian packaging

A plastic-metal hybrid "franken-can" commonly used by cafes for cold drinks has won the Unpackit Award for Australia's Worst Packaging. (Supplied: Australian Marine Conservation Society)

Plastic and metal "franken-cans" have been named Australia's worst packaging in the country's first Unpackit Awards.

Organised by the Australian Marine Conservation Society, WWF-Australia and the Plastic Free Foundation, the awards highlight the shonkiest and most innovative packaging.

The best packaging award went to The Udder Way for its refillable 18-litre milk kegs.

It has become a popular way for cafes to serve up matcha or iced coffee, but environmentalists say single-use "franken-cans" are among the worst of Australia's packaging.

The thick plastic jar is usually filled onsite and sealed with an aluminium top welded to the vessel, making it disposable after a single use.

And the hybrid product has just taken home the gong for the worst packaging in Australia at the inaugural Unpackit Awards.

Judges reviewed hundreds of nominations from the public before naming "franken-cans" the worst packing in the country. (Supplied: Australian Marine Conservation Society)

"These franken-cans tick every box for problematic packaging," Cip Hamilton from the Australian Marine Conservation Society said.

"They're made for single use, built for on-the-go consumption and likely to end up as street litter, are not accepted by container refund schemes and almost impossible to recycle.

"We've got the solution — it's a reusable cup. Let's stick with that."

The Unpackit Awards were organised by the Australian Marine Conservation Society, WWF-Australia and the Plastic Free Foundation, to shine a light on everything from the shonkiest to the most innovative packaging.

Hundreds of nominations were received from members of the public before the best and worst awards were decided by a panel of judges.

Coles, Woolworths and Aldi received a "dishonourable mention" for wrapped avocadoes in plastic netting that shed microplastics.

Three major supermarkets received a "dishonourable mention" for selling wrapped avocadoes in plastic netting. (Supplied: Australian Marine Conservation Society)

"About half of the nominations from the Australian public were made for plastic packaging around fruit and vegetables in our major supermarkets," Plastic Free Foundation executive director Rebecca Prince-Ruiz said.

In a statement, an ALDI spokesperson said the supermarket was on an "ongoing sustainability journey", with 87 per cent of its exclusive brand packaging either recyclable, reusable or com