The Shape of Acid: Looking our Wine Square in the Eye

After peaking the vertical acid structure and feeling like I could identify horizontal acid shapes in my sleep, I expanded my acid shape journey: squares, waves, rainfalls, and more.

Let’s look at some “square-like” shapes next!

The Set-Up: Let’s Get Fair and Square

To compare two different square-like acid shapes, I again chose two grape varieties with naturally high levels of acidity: Assyrtiko and Albariño. 

This keeps acid intensity out of mind as we sip so we can focus entirely on where the wine hits. Both of these varieties share a remarkably similar flavor palates: crisp, citrus, zesty lemon, and minerality.

To taste them in their purest expression, I selected benchmark examples from their respective homelands: an Assyrtiko from Greece and an Albariño from Spain. 

The Assyrtiko Sandwich: Feredini Art. Karamolegos Winery 2023 (Santorini, Greece)

• Aroma:  Lime, earthiness, light smoke, salinity. 
• Flavors: Light lean and crisp citrus – lemon peel, lime zest. Minerality, dry stone.
• Acid: High, with an almost square-like acid feel in my mouth.

Drunk alone, this wine makes me want to stretch my lips long and pucker at the same time. 

The acid locks into a square-like perimeter. If I pucker, it softens the top and bottom pressure; if I grimace, it lessens the tension on the sides.

But I pucker more. It’s clear the acid is strongest at the top and bottom of my mouth.

The acid is strongest at the top and bottom. It isn’t a full-mouth sensation; it doesn’t surround my mouth. 

Taking a sip after the Albariño, the roof-and-bottom palate “sandwich” feels even more extreme. I only want to pucker to counteract the crushing horizontal lines.

The Albariño Anvil: Fento Wines Eulogio Pomares “Bico da Ran” 2025 (Rías Baixas, Spain)

• Aroma:  lemon and lime peel and zest.
• Flavors: crisp and zesty, intensely lemon and lime, with layers of zest, peel and pith.
• Acid: High, prickly all over mouth. Almost like a spritz-like mouthfeel. 

At first sip, the wine threatens to occupy a full square shape. But as I focused, the sensation on the roof of my mouth subsides. The acid migrates entirely to the columns on the side of each cheek. 

It created a shape more like this:

I————–I

Basically, it was an anvil…or just the sides of the box. I think that Master of Wine Nick Jackson in his book “Beyond Flavour” referred to it as “wall-to-wall.”

Sipping the Albariño directly after the Assyrtiko highlights this contrast beautifully: the center clears out, and the acid clamps down hard on the cheeks.

The Structural Summary: Closing the Box

The Assyrtiko stretched across my palate, but it was far more than a flat line. It built the horizontal boundaries—the floor and the ceiling—like a structural sandwich.

The Albariño reached across my mouth, but it wasn’t a standard linear profile either. It erected the vertical walls on my cheeks, shaping the sides of the box.

Because these two high-acid, saline, citrus-driven wines can easily be mistaken for one another in a blind tasting, mapping these “square” metaphors is exactly how you solve the puzzle. One wine frames the top and bottom; the other locks in the sides. Together, they complete the square geometry of acid.