It's no coincidence that radlers, the refreshing drink that combines lager beer and lemon soda, has the same name as the German word for cyclist.
Legend has it that innkeeper Franz Xaver Kugler owned a beer garden outside of Munich along a popular bike trail. One summer day in 1922, a large group of thirsty cyclists — some versions of the story claim as many as 30,000 — descended on his establishment, causing him to run low on beer. The resourceful host responded by mixing beer with a carbonated lemon soda he happened to have on hand. The sweaty cyclists loved the thirst-quenching quaff so much that the radler — named after the cyclists — was born.
Whatever the origin, the radler remains a popular summer drink in Germany and goes by many names, depending on the region. (In the north it's called Alsterwasser, a reference to the water of the Alster River that joins the Elbe River in Hamburg.) Radlers are typically a nearly even blend of lager beer and tart, carbonated fruit soda like those from Pellegrino. Light, sweet-tart and with alcohol usually in the 2% range, they make for a great summertime refreshment.
Of the examples currently available, Sam Adams' Porch Rocker lemon radler best matches my recollections of the radlers I enjoyed during a long sojourn in Germany. Porch Rocker is a perfect blend of beer and soda. You taste the sweet, grainy malt of the Helles lager. You taste the subtle herbal/spicy hops. The sweet-tart lemon soda just balances the beer, but the two merge without one covering up the other. At 4% alcohol, it's stronger than most.
At 2% alcohol, Zitrone from the Stiegl Brewery in Salzburg, Austria, is more typical of the style. It's a bit sweeter than Porch Rocker, but not enough to interfere with the refreshment. The profile is mostly lemon, with just enough lager character to remind you that it's there. This is a light, bright, slightly tart and slightly bitter lemon soda that will quench your thirst on a hot summer day.
Lemon isn't the only fruit going into radler these days. Stiegl offers two other versions — himbeere (raspberry) and grapefruit.
Himbeere Stiegl Radler is mostly raspberry with little presence of the underlying lager beer. There is a bit of raspberry tartness there, but it's nearly overwhelmed by sugary sweetness. Too sweet, I feel, to take on the summer heat.
The Grapefruit Stiegel Radler is the brewery's best-known and best-tasting radler. This one is all about the grapefruit. Like sweetened grapefruit juice, the sugar is well-balanced by acidity and pithy bitterness. The acid tartness and lingering bitterness make it fresher and less soda-like than Stiegl's other radlers.