The mad scientists at the Yarra Valley’s award-winning Four Pillars Distillery will release their second vintage of Bloody Shiraz Gin this Saturday – which just happens to be World Gin Day.

Bloody Shiraz Gin is the brainchild of Four Pillars’ chief distiller, Cameron Mackenzie, who also happens to be a former Olympic athlete, a combination of talents that just seems unfair.

McKenzie was hanging out with his friend Rob Dolan at the latter’s winery in Warrandyte last year when a small 250kg parcel of Shiraz grapes rocked up unannounced. Dolan didn’t know what to do with it. Mckenzie had an idea for an experiment.

The grapes were left in contact with Four Pillars’ high-proof Rare Dry Gin for eight weeks and plunged each day. (The Rare Dry Gin was awarded Double Gold status at the San Francisco World Spirits Competition in March, the only Australian gin to do so.) After the spice and pepper of the Shiraz had infused with the citrus and juniper notes of the gin, the resultant juice was gently pressed, bottled, and the ABV adjusted to 37.8 percent.

There were only 600 bottles or so, but that was enough to make an impression. On World Gin Day last year, Bloody Shiraz Gin – named for the French “saignée,” or “bleeding,” which is a method of rosé production that involves bleeding off the grape juice after limited contact with the skins – was the distillery’s best-selling product. The entire run sold out within weeks.

This year, production of the gin has ramped up. Instead of waiting for grapes to appear out of thin air, Four Pillars sourced them specifically. Instead of a mere 250kg, it opted for two tonnes. The fruit was kept whole, rather than crushed, and the bottled result is unfiltered and unfined. Bloody Shiraz Gin is deep purple in colour, turning pink when mixed with tonic or soda, and is available online or from the laboratory – sorry, distillery – door.

World Gin Day is a worldwide series of tastings, masterclasses, lunches and dinners organised by the London-based Gin Monkey website.

Now in its eighth year, it includes events in Sydney, Melbourne, Adelaide, Perth, Canberra, the Yarra Valley and Pontville, Tasmania.