Naviluna’s Velvet Stout Bar

By David Nilsen

Naviluna Artisan Chocolate in Mysore, India, reached out to me recently a new bar they were releasing they thought I’d be interested in, and they were right. As fate would have, Naviluna was one of the first craft chocolate makes I ever had the chance to try, though which bar it was is lost to memory. When the small box arrived from the other side of the world, I eagerly opened it and set eyes upon their Velvet Stout-Infused Bean to Bar 69% Dark Chocolate “with a touch of rasa bale”, a type of banana.

There are a lot of different ways to make chocolate using beer or beer ingredients, but one of the most fascinating—and one that results in some of the richest complexities of flavor—uses reclaimed cacao nibs used in the making of chocolate-infused beer. I first same across this technique from Somerville Chocolate years back, and I would love to see more makers and brewers experimenting with it.

Naviluna first tried this in late 2019 with an undisclosed brewery in Kolkata, but the bars never saw the light of day, as their release coincided with the onset of the pandemic. Half a decade later, they’ve picked up the project with this lovely new bar.

The Velvet Stout bar has been made in collaboration with an undisclosed craft brewery in Bangalore. The brewery—which Naviluna owner David Belo refers to as “Brewery B” to differentiate it from “Brewery A” from before the pandemic—made three batches of a stout using cacao nibs from the Kerala state in India. The nibs were unroasted, as Naviluna and Brewery B wanted to maintain more fruitiness from the beans rather than a roasty character. They sat in the stout during post-fermentation conditioning for two weeks, and were then removed, vacuum sealed, and sent back to Naviluna.

Then Naviluna was tasked with drying them back out and turning them into chocolate without losing the delicate nuances they’d acquired while resting in the beer. They settled on drying the nibs at 35° C (95° F) for over 50 hours. The low temps preserved as much character as possible without bringing forward any harshness.

“From my experience during the first project in 2019, I knew the biggest challenge was conching and any heat generating process as it activated the residual hops oils on the cacao, making the chocolate bitter,” says Belo. “This is the reason for the low dehydration temperature. We found that anything over 40° C really brought out aggressive bitterness from the hops, which as viscerally evident on the palate, in spite of the actual residual hops content on the cacao nibs being less than 0.01% by weight.”

This is a curious finding, though I don’t doubt the sensory analysis. Hop bitterness in beer comes from alpha acids, organic acids that in their natural state are not all that bitter or water soluble. In brewing, hops get boiled, and the high temperature isomerizes those alpha acids (isomerization is when a molecule is physically reconfigured into a different molecular structure, without adding or removing molecular components) into what we call iso-alpha acids, which are significantly more water soluble and perceptibly bitter.

This raises a couple questions about the bitterness issue Naviluna ran into at relatively low temperatures. First, isomerization only happens temperatures close to twice the ones they were using to dry the nibs. Second, since the nibs rested in finished beer, post-boil, most of the alpha acids are already isomerized, meaning they’re in their most bitter state to begin with.

I’m not sure how to reconcile those issues, and I’d love to taste the nibs dried at the higher temperature to try to identify what’s happening. Possibly other volatiles are being lost that increase perceived bitterness? Maybe another organic compound in the hops and/or nibs converts to a more bitter state? This is really interesting, and might warrant some experiments.

Naviluna was similarly careful in how they conched the nibs after drying, to both preserve some delicate fruit notes and to avoid bringing out the mysterious bitterness.

“During conching a difficult balance had to be struck to remove acetic acid without stimulating increased hops-induced bitterness,” says Belo. “Whilst conching, a lovely raspberry note was emerging from the cacao liquor, but every time we’d pursue its development, the hops would take over and give the liquor that aggressively herbal bitterness. It took a while to find the balance.”

The finished bars were made with cacao conched at low temperatures for about 36 hours.

To accent the cacao and the beer flavors it carried, Naviluna garnished them with candied bananas the Rasa variety from the district of Nanjungud. Belo says they’re known for their juicy, tangy, and distinctive flavor, and they were added to provide a tangy offset from the “heavy collage of flavor” emanating from the malted barley, hops. and cacao.

In tasting the bar, the banana does play an important role in softening the landing of those more aggressive components. For me, it was their subtle sweetness that provides bumper rails for the other flavors. There’s a cool layering of earthy, roasty notes from the cacao and the stout it rested in, along with an unmistakable flavor of dark barley malt that comes through clear as day, occasionally leaning into an agrarian hay-like note. Bitterness flits around the edges and between the other components, but only as an accent, never getting out of hand.

Belo wanted to pursue this collaboration not just to create interesting flavors, but explore the nature of collaboration itself, which often gets cited for social media marketing but doesn’t always represent true creative cooperation. He was inspired by the work of Andy Warhol and the Velvet Underground in the 1960s, which led to the iconic banana artwork on the wrapper.

“In terms of the art direction, the theme explored ideas around collaborations, art, craft, industrial production, and expression,” he says. “Nico, who sang on the first Velvet Underground record, was herself from a long line of German master brewers, which is just one of several conceptual threads that run through this exhibition release.”

The iconic singer, who died tragically in 1988 after a bicycle accident, was born into a well-to-do brewing family who had founded Päffgen Kölsch in Cologne in 1883.

Naviluna’s Velvet Stout bar is a testament to the kind of fascinating results that can come from true curiosity, experimentation, and collaboration between creative producers in different fields. I’m grateful to get to taste it and learn from it.