Bar tools: is copper proper?

The copper-plated items from Sainsbury's with the ingredients for a White Lady

I was marching through the mega-Sainsbury’s supermarket at Beckton, hoovering up Prosecco deals, when my eye was caught by a display of tools for the home bartender. What made them unusual was that they were made from steel plated with copper. In fact in this case they turned out just to have shakers and ice buckets, but by chance a couple of days later I was checking out a new restaurant in my neighbourhood when I saw, behind their freshly fitted-out bar, a whole array of copper plated tools, including hawthorn strainers, bar spoons, jiggers and tongs. I subsequently discovered that Cocktail Kingdom sells all this stuff, which I suspect is where the restaurant got it from. They even sell copper-plated speed pourers.

What was the thinking here? In truth I suspect it is just meant to look fancy: Cocktail Kingdom also do silver- and gold-plated equipment. And let’s not forget that none other than Jerry Thomas himself, once he got rich and famous, adorned both himself and his bar tools with precious metals and jewels.

But I couldn’t help wondering what effect the copper might have on the drinks being made. Gold is famously unreactive, as is the stainless steel that this equipment is made out of. But copper, like aluminium, is reactive. In fact I have a copper bowl designed expressly for whipping egg whites, as the copper is said to react with the egg and help to stiffen it. And given that cocktails often involve some acidic ingredients, would contact with the copper give the drink a metallic taste?

Two White Ladies

There was only one way to find out: a head-to-head comparison between the copper item from Sainsbury’s and a stainless steel shaker I already had. I decided to make a White Lady cocktail because it not only contained a shot of lemon juice, but also egg white—so I could test the egg-stiffening theory. I used 1¾ shots gin, 1 shot Cointreau, 1 shot lemon juice and the white of 1 egg. Each was shaken hard to froth up the egg white. (For simplicity’s sake I refrained from “dry shaking”, either before or after the ice, a practice some use to get a thicker texture from the egg white.)

I can’t say that I detected a metallic taste in the cocktail made with the copper shaker. Initially I didn’t fine-strain, and the drink from the copper shaker had a different texture because it actually had small pieces of ice in it—perhaps I unconsciously shook that one harder? After fine straining the two drinks I actually felt that the drink from the steel shaker had a richer texture, though Mrs H. said she couldn’t tell them apart.

The cap and shoulder of the shaker are copper-plated on the inside too, while the body is not

As another test, I made a brace of Daiquiris. I even added the ingredients to the upturned cap and shoulder of the copper shaker (these bits are copper-plated on the inside for some reason, while the body of the shaker is not), so they might have a chance to interact before I added the ice and shook. My feeling this time was that the drink from the copper shaker had a different, slightly “off” taste. But then it struck me that each drink had included the juice of a whole lime—so I could just be tasting the difference between two different limes. So I repeated the experiment, this time blending the juice from the two limes before dividing it between the two shakers.

The result? Nothing that I can detect. Copper is widely used for making stills in the distilling industry because it is said to absorb sulphurous impurities, so clearly it is viewed as a reactive component in the presence of alcohol. But it doesn’t seem to affect the taste of cocktails at the end-user stage.

You can see the ice particles in the cocktail
on the left (click to enlarge)

One thing that did emerge from this comparison, however, was the difference in shaker design. I don’t think I can blame the shape or construction of the copper shaker for the preponderance of ice particles in my White Lady—that is more likely to be down to poor technique on my part, or just being too lazy to fine-strain.* But I did notice that it seemed rather unwilling to pour the finished drink, compared to my trusty steel shaker. Looking closely you can see that the latter has long, narrow slits around the side of the built-in strainer, in addition to the circular holes, while the copper shaker just has the holes, making it slower to pour. Bar pros all tend to use Boston shakers anyway (either glass-and-tin or tin-and-tin), but I rather like the iconic shape of the Manhattan shaker. So if you’re in the market for one, it might be an idea to look at the design of the strainer.

Note the extra slots around the side of the strainer on the right. Even though the holes are smaller
it pours more quickly and smoothly than the copper one

* Japanese bar legend Kazuo Uyeda, also a fan of the Manhattan shaker, doesn’t fine-strain his cocktails as he says he likes the fine ice particles in the drink.