$12 for a drink made with leftover banana peels? My strange night out at Norwegian Cruise Line's new 'zero-waste' cruise ship bar

Editor’s note: TPG’s Gene Sloan accepted a free trip from Norwegian Cruise Line to attend this week's unveiling of Norwegian Prima. The opinions expressed below are entirely his and weren’t subject to review by the line.

It turns out a drink made with banana peels isn't nearly as weird as you might think.

As I sidled up to the bar Friday night at the Metropolitan, the much-ballyhooed new "zero-waste" cocktail lounge on Norwegian Prima, I was expecting to be confronted with highball glasses stuffed to their sugar-rimmed tops with browning banana peels, overripe strawberries and day-old croissants.

The pre-launch promotion for the venue had left me bracing for just that sort of oddball experience. It promised "sustainably focused" drinks made with all sorts of otherwise-heading-for-the-trash food items leftover from the new Norwegian Cruise Line ship's eateries — banana peels and hardening croissants included.

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Honestly, I was envisioning drinking mushed-up versions of the things that normally go into my garbage disposal — and paying $12 a pop for the privilege. More power to Norwegian if it can get people to do that.

But the made-with-banana-peels Primadonna cocktail I ordered just moments after grabbing the last white leather seat at the venue's marble-topped bar turned out to be as un-weird as it was delicious.

There really were banana peels in it, but none that you could see. As Lovely, the bartender, explained, the back-of-house staff at the venue makes a homemade banana peel syrup by boiling banana peels collected from around the ship. It's boiled down so much that it turns into a nearly clear, sweet liquid used to infuse the Primadonna and other drinks at the bar.

The Primadonna also is made with 15-year-old Flor de Cana ECO rum, walnut bitters and orange bitters.

Put it all together, pour it over a single large square ice cube, and what you get is something that tastes like a fairly traditional, old-fashioned-y drink, not something new and concocted.

Related: The ultimate guide to Norwegian Cruise Line

Which, as it happens, is sort of the point with the Primadonna. As Lovely noted, it's basically an Old-Fashioned — one where the ECO rum takes the place of the whiskey that's normally in an Old-Fashioned, and the banana peel syrup takes the place of the sugar cube.

The ECO rum, for the record, is "ecofriendly and sustainably produced," according to its maker, being carbon neutral and fair trade certified and packaged in sustainable materials. The bottle that it comes in is made from recycled glass.

All the drinks at the Metropolitan bar are made with such sustainably focused spirits — a new concept for Norwegian. The brand has been getting more into sustainable drinks for several years, but this is the first time it has dedicated an entire bar to the idea. It's billing it as the first sustainable bar at sea.

The bar is just opening this week as Norwegian Prima begins a non-revenue preview sailing for media and travel agents in advance of its maiden voyage with paying passengers next week.

There are 11 special sustainable drinks at the Metropolitan in all, promoted on fancy tablets that sit atop tables. The tablets have pictures of the drink options and their unusual ingredients zipping by (a bit too fast) in a continuous stream.

Related: Getting the most out of the Norwegian loyalty program

Carbon neutral and fair trade Flor de Cana rum serves as the base of many of the sustainable cocktails. Most of the rest are made with Avorza vodka, which is billed as certified organic, vegan, gluten-free and kosher.

It's all very trendy and, some might say, a tad gimmicky. A cynic might dismiss it as little more than virtue signaling on the part of Norwegian. Sustainability is a selling point now for all sorts of consumer companies, driven by consumer demand. It's good marketing. But after an hour sitting with Lovely at the bar, watching her make up all kinds of mind-boggling mixtures using ingredients that otherwise would be headed to the scrap heap, I got the feeling that this was more than that.

Norwegian has seen the future when it comes to zero waste on ships, and — in addition to a lot of other things like using less-polluting fuels and removing plastic bottles — it includes getting someone to drink away all those banana peels.

In the name of research, I asked Lovely to make me another sustainable cocktail from the list. Having loved the Primadonna — not surprisingly, since I'm a big Old-Fashioned fan — I thought about asking for a similar drink called the Bananaruma. It's made with 4-year-old sustainable Flor de Cano rum stirred into the banana peel syrup and Angostura bitters. I also eyed the Bananarum-ble, which paired the sustainable rum with Peychaud's bitters; the banana peel syrup; pineapple, lime and cherry juice; and pineapple peel.

Note that the pineapple peel also is collected from eateries around the ship.

In the end, I settled on the Croissant Mai-Tai, for no other reason than it supposedly is made out of the day-old croissants that are leftover from the ship's breakfast eateries. How fabulously odd.

Alas, as with the banana peel drink, I could not see direct evidence of the leftover ingredient when I was presented with the creation. My vision had been of a traditional Mai-Tai with a past-its-prime croissant unceremoniously plunked down into it and sticking up over the top in lieu of one of those paper umbrellas. What a great Instagram post that would make. Alas, it was not to be.

As Lovely explained, the leftover croissants are pulverized and cooked down to a syrup with a tad of cardamom added for good measure.

Lovely warned me in advance that the Croissant Mai-Tai — made with rum, Cointreau and lime juice in addition to croissant syrup — tasted like a dessert, and indeed, it did. Too much for my taste.

I have now learned that I am not a croissant-infused drink fan.

Hoping for better luck with a third choice, I asked Lovely to craft me yet one more drink from the list. Make it a surprise, I said. Something wonderfully sustainable and different than anything I had yet tried.

What arrived was La Madrina, made with Avorza Ultra Premium Organic vodka, Aperol, strawberry and orange "oleo," lime juice, ginger beer and a dehydrated orchid (the latter element adorning its top).

The big sustainable element here, other than the organic vodka, was the strawberry and orange concoction, which Lovely told me was made with the leftover bits of strawberries in the ship's kitchens and otherwise-to-be-discarded orange peels.

Again, it all gets boiled down into a sugary syrup.

As for the verdict on La Madrina: If you're a Moscow Mule fan, you'll love it. It's basically the same thing, albeit a bit sweeter with the addition of the strawberry-and-orange mix.

I'm so-so on Moscow Mules. Ginger beer in drinks just adds a bit too much spice for my taste.

But I'm a firm believer in saving the environment. So ... I drank it down to the last drop. It didn't seem right to waste it by leaving it unfinished. Not at this bar.

Don't say I haven't done my part.

TPG's Gene Sloan will be reporting live from Norwegian Prima over the coming days as it sails from Reykjavik, Iceland, to Amsterdam on a non-revenue preview voyage for media and travel agents. You can find all of his dispatches on his author’s page.

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