Are blue lattes summer's hottest drink?

“It has a strong, seaweed-type smell.”

Yep, meet the new “It” vegan take on coffee — a smurf latte.

The blue drink is made of algae, lemon, ginger agave and coconut milk, costs $8 and is becoming a social media sensation after debuting on the menu at the Australian eatery Matcha Mylkbar in Melbourne this week.

Matcha Mylkbar co-owner Mark Filippelli said the vegan cafe had sold at least 100 of them in four days.

“It tastes like a warm lemon, ginger and honey tonic,” Filippelli said.  “We don’t use honey, as it’s not vegan, so we use agave instead.”

And while one of Filippelli’s colleagues described it as tasting like “sour milk” to Broadsheet, Filippelli said the smurf latte was actually much more pleasant to the palette. But he admitted it “does have quite a tart after taste”.

Algae is an edible freshwater plant and is a known source of antioxidants, Filippelli said. “It is such a powerful antioxidant that one gram of it every day has a huge (health) benefit,” Filippelli said.

But with an $8 price-tag, Matcha Mylkbar’s smurf latte is hardly an affordable replacement for your daily takeaway coffee.

“The average daily cost of one gram (of algae) is over $3 so that’s why we’re charging $8,” Filippelli said of the cost. “A lot of people will just come and try something new ... we’ve had some customers who have come back and had it every day.

“Because it is so pretty, it is Instagram-able.”

Matcha Mylkbar’s menu includes a beetroot latte ($5), mushroom latte ($7), turmeric latte ($6) and apple pie latte ($5), along with a vegan take on eggs (made of plant-based ingredients) and soy “chicken” burgers.