It was a trip to America in March that inspired the latest beer of the Geelong brewery Two Birds Brewing.
''We ended up eating a whole lot of fish tacos and drinking amazing beer in San Diego,'' says co-owner and brewer Jayne Lewis. ''We decided to make a beer that evoked those flavours. So we've used a little bit of corn, thrown in coriander leaf and a whole stack of lime.''
The resulting beer, a hoppy wheat beer named Taco, may sound kooky but such experimental brews are becoming more common.
The Two Birds brew is just one of a host of beers flavoured with unusual ingredients that will be served at the Great Australian Beer SpecTAPular, which runs from May 24-26 at the Royal Exhibition Building, Carlton.
Some will dismiss such beers as novelty items, but that's not the case, says Craig Wealands, the owner and brewer at Wagga Wagga's Thirsty Crow.
He has collaborated with the William Bull Brewery in Bilbul, New South Wales, on an oak-aged American stout made with orange zest and espresso for the festival. ''We brew a beer every year for Oktoberfest called Liquid Bacon,'' says Mr Wealands, 31. ''It's a smoked beer. In Wagga, it's a novelty because it tastes like bacon, but in Bamberg, in Germany, they've been brewing that kind of beer for hundreds of years. It's a matter of perception.''
The current fashion for innovative brews is being driven by the craft-beer movement that began in the US. But beers have been flavoured with ''unusual ingredients'' (that is, anything other than hops) for centuries. Belgian beer is cherished around the world partly because Belgian brewers use fruit , spices and herbs. This fashion for trying unusual ingredients has resulted in some beers that may appear beyond the pale.
A British brewery, Sharp's, once produced a beer made with offal, for example, and a recent project at Rogue Ales in the US saw a brew fermented with yeast taken from the brewer's beard.
There are limits, says Mr Wealands. ''Probably the wildest thing I've ever put in a beer is oysters, into an oyster stout,'' he says. ''I'd say no to putting 99 per cent of things that exist into a beer.'' That still leaves plenty of options, says Ms Lewis, 33, who co-owns Two Birds with Danielle Allen. ''There are so many things that work in a beer,'' she says.
Much of her inspiration comes from things happening in the food world, Ms Lewis adds. Two Birds produced a Japanese-inspired beer last year made of seaweed, green tea and brown rice.
''One of the best things about travelling the world is trying the food, and sampling the flavours that exist,'' she says. ''It's cool to capture that in a beer.''
The Age is a media partner of GABS, gabsfestival.com.au.