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5 March 2026

From Coffee Grounds to Bitterball: Closing the Loop at De Zeeuwse Stromen

What if your morning espresso could become your favorite beachside snack by sunset? From Coffee Grounds to Bitterball: Closing the Loop at De Zeeuwse Stromen is more than a catchy phrase—it’s a tangible, tasty example of circular hospitality. Here’s how we transform collected coffee grounds into oyster mushrooms and serve them as delicious bitterballen at our Beach Pavilion De Haven van Renesse, less than 300 meters from the hotel and open 365 days a year.

In this article, you’ll learn how the loop works, why it matters, where to try it, and how it fits into a broader Green Key Gold approach that keeps nature front and center—without compromising comfort.

What “From Coffee Grounds to Bitterball” Means

At De Zeeuwse Stromen, culinary pleasure and circular thinking go hand in hand. We collect coffee grounds from the hotel and our nearby beach pavilion. Periodically, and in combination with deliveries, our supplier Bidfood takes these grounds to the Amsterdam-based company GRO. GRO grows oyster mushrooms on this nutrient-rich material. Those oyster mushrooms return to our menus in multiple ways—most notably in the tasty oyster mushroom bitterballen served at De Haven van Renesse. That’s a loop you can taste.

You’ll also see the same principle in our restaurant and bar: oyster mushroom croquettes from De Ambachterie use a filling made with oyster mushrooms grown on our own coffee grounds, and our Orangecello (Dik & Schil) liqueur gives new life to the orange peels left after we press fresh juice. Different products, same idea—minimize waste, maximize flavor.

How We Close the Loop: Step by Step

1) Brew and collect

2) Backhaul with Bidfood

3) Grow with GRO

4) Serve at the beach

Why Closing the Loop Matters

Circular systems aim to keep resources in use for as long as possible through reuse, recovery, and regeneration. Coffee grounds are rich in organic matter; using them to grow mushrooms is a widely recognized example of upcycling. The benefits are straightforward:

This is the kind of visible, meaningful action that turns abstract sustainability goals into everyday experiences.

Beyond Bitterball: Our Green Key Gold Actions

Our circular bitterballen aren’t a one-off—they sit within a comprehensive approach recognized by the Green Key Gold certification. Green Key is the largest sustainability hallmark for tourism and recreation in the Netherlands, and this seal indicates we do more than regulations require while maintaining comfort and quality. Highlights include:

These choices reflect a simple idea: let’s be as little a nuisance to nature as possible, together.

Where to Taste—and What Else to Try

For even more local inspiration, check our Location & tips for nearby culinary spots, beach clubs, and family-friendly activities.

Quick Answers (Great for Snippets)

How does De Zeeuwse Stromen turn coffee grounds into bitterballen?

We collect coffee grounds at the hotel and beach pavilion; Bidfood periodically picks them up with deliveries; GRO grows oyster mushrooms on the grounds in Amsterdam; we serve those mushrooms as oyster mushroom bitterballen at De Haven van Renesse.

Where can I try the bitterballen?

At Beach Pavilion De Haven van Renesse—less than 300 meters from the hotel and open every day, year-round.

Who grows the mushrooms?

GRO, an Amsterdam-based company that cultivates oyster mushrooms on spent coffee grounds.

Is this part of a larger sustainability plan?

Yes. We hold the Green Key Gold certification and run multiple initiatives including a biodigester, solar thermal panels, heat recovery for our pools, LED lighting, water-saving measures, and more.

Practical Takeaways: How You Can Help Close the Loop

The Bigger Picture: A Beachside Loop You Can Taste

From Coffee Grounds to Bitterball: Closing the Loop at De Zeeuwse Stromen shows how small actions add up. Coffee grounds that might have gone to waste become gourmet ingredients. heat that could have dissipated now warms our pools. Kitchen scraps power a biodigester that helps heat our rooms. It’s practical sustainability—visible, flavorful, and shared.

Ready to experience it yourself? Visit Beach Pavilion De Haven van Renesse for the oyster mushroom bitterballen, drop by Café 16 Kwadraat for a relaxed drink, and explore our Sustainability and Green Key Gold pages to see how we keep raising the bar. Book your stay at De Zeeuwse Stromen and taste what a circular seaside escape can be.