Wine investors always seek a Penfolds Grange, arguably one of the best red wines in the world and certainly the most expensive in Australia. So revered are its special editions that prices jump from four to six figures (or more) when one resurfaces on the auction block a few years after launch. If you’ve missed the boat on previous collectibles, get ready to pounce on the recently unveiled G5, the third and final release in Penfolds’s highly successful, multi-vintage G series.

The first – G3 – debuted in 2017 and is a blend of the 2008, 2012 and 2014 vintages. The G4 that followed three years later is a blend of four vintages: the 2002, 2004, 2008 and 2016. So the G5 is made from — you guessed it — five vintages, from the years 2010, 2012, 2014, 2016, and the yet to be released 2018, which will only hit the market in August.

Blending vintages is fairly common when making fortified wines and some champagnes in order to get a consistent style or to achieve a taste profile no single vintage could offer. The opposite is true for still wines for multiple reasons that range from the pragmatic to the arrogant. Smaller wineries may lack a big enough cache of reserve wines to play with because they ship whatever they can make from any harvest. Other winemakers might argue that blending vintages is an affront to the expression of terroir.

Penfolds has none of these concerns. But Chief Winemaker Peter Gago (pictured below) still thinks that getting a bunch of vintages together to be matured in barrel once more is “just not a sensible thing to do”. The winemaking team essentially had to crack open perfectly sellable, highly valuable bottles for a mad scientist-style mixing experiment with no guarantee that the final product would be palatable.

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Penfolds chief winemaker Peter Gago.

But the G5 turned out to be heavenly. “It has a subliminal, volatile character that’s just shy of being a fault. There’s lovely red currant and liquorice on the nose, and no rough edges on the palate. It’s not too big or oaky, even though each vintage was aged in 100 per cent new oak,” shares Gago.

The exact proportions of the vintages that went into the blend are a secret, but Gago admits each component contributes to at least 10 per cent of G5. The fruit is sourced from the Barossa Valley, McLaren Vale, Clare Valley and Wrattonbully, and is predominantly shiraz, with just 3 per cent of it being cabernet sauvignon. “We weren’t trying to make something different from Grange. We wanted to capture the essence of it.”

Even if the G series wasn’t so inherently risky to make, Penfolds was always going to conclude with the G5. Gago provides two reasons. “One is to respect the people who have invested in this. They have something finite and collectible, like our Penfolds Ampoule,” he says, referencing the hand-blown glass vessels that hold the 2004 Kalimna Block 42 Cabernet Sauvignon. Only 12 were made. “The other reason is — if we do a G6 or seven or eight, you’ve got a lovely wine, but it will be a solera, like sherry or port.” He adds: “Each of the vintages in the G5 contributes something special to the blend, like the lovely completeness of the 2010 or the voluptuousness of the 2016. I think of it as a weighted average.”

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Penfolds G5 wine in the box.

Coinciding nicely with the 70th anniversary of Grange, only 2,200 bottles of G5 will be available with a recommended retail price of $4,998 for 750ml. This will no doubt skyrocket, but Gago believes they’ll be worth drinking, if nothing else. “In 50 years, I’m hoping people will look back on these and think, ‘These were classic, Australian, Penfolds reds’ rather than, ‘Oh, they got away with that.’” Register your interest at penfolds.com.