And then you added the simple syrup to the strained infusion–the climactic step–and the whole works turned cloudy. I feel ya. It happened to me.  Don’t dump it! There’s a fix. It’s an unusual process, but it is pretty cool. You can clarify your Campari with what’s known as a milk wash.

Why Homemade Campari Turns Cloudy

Polyphenols are compounds found in many of the bitter botanicals used in making alcohol infusions like Campari. They are expressed in the botanicals’ essential oils. The step in our homemade Campari recipe where you add the water-based simple syrup to the alcohol-based infusion is where things can get cloudy. The introduction of the water in the simple syrup to the alcohol in the infusion, with its small percentage of essential oils, can trigger a microemulsion that turns the clear liquid cloudy.  Campari is not ouzo or absinthe, but you know how those anisettes become cloudy when water is added? This is called a louche effect, and in the case of an anisette, it’s intentionally created when water is added to a serving glass of the clear spirit (think of the ritual of pouring water over a sugar cube and into a glass of absinthe, which triggers the cloudy haze responsible for white fairy lore). But that louche effect is not at all what you want with a ruby-hued spirit like Campari; haziness is not part of the drink’s lore. When I made my batch of DIY Campari, I tinted the simple syrup an enticing red with food coloring, but upon adding that tinted syrup to the strained infusion, it instantly turned a brackish, murky brown, and my spirits (both emotional and drinkable) plummeted. I took a sip and the stuff tasted awful, like the worst medicine you ever had to drink as a kid. What was going on? It may be in part a question of temperature. If those two liquids are not at the same temperature when you combine them, cloudiness can ensue. According to the study Examining the Temperature Dependence of Louche Formation in Absinthe, “both the maximum turbidity and the fraction of alcohol at maximum turbidity are temperature-dependent.” TL;DR? This blog post on Clawhammer Supply might clarify (no pun intended): “Oils from plant material (when distilling essential oils) can cause cloudiness as well. Interestingly, at low concentrations of oil may present as crystal clear initially, but after being chilled, the liquid will develop a cloudy haze. This is called a ‘chill haze’.”  Interestingly enough, I’d taken the temperatures of both the alcohol infusion and the simple syrup before combining them; they were the same ambient room temperature. But I’d dumped the syrup into the alcohol rather than adding it in a trickle, which might have some bearing, too. In a thread on our homemade Campari recipe, commenter Erik Farrar shared, “This is indeed a louche effect—the alcohol-soluble oils are coming out of solution when the relative water content increases. At minimum, try adjusting how you’re adding the (water-based) simple syrup: use room-temp syrup, add it SLOWLY while mixing constantly, and consider adding it in batches (say, like a quarter of the expected each time), letting it rest and co-mingle in between additions. This might help ensure that the percent ABV stays homogenous and high enough to retain the oils.” Adding the syrup slowly might also be key to keeping your homemade Campari clear. The harm was already done in my case, though. The fix? Reach for a carton of milk.

What Is Milk Washing?

The proteins in milk bind to the polyphenols we mentioned earlier. If there’s acid in the liquid you’re adding the milk to, that milk will curdle, and as it does, it traps the polyphenols. Slowly strain out those curds and magic ensues. Not only does this make the liquid clearer; it removes some of the bitterness, as well as a number of tannins.  Milk washing has been around for ages. The centuries-old drink milk punch is an example. Milk washing has enjoyed a resurgence in cocktail culture in recent years, as it creates a smoother, rounder spirit. It’s also messy and somewhat involved, but resurrecting your cloudy Campari from the dead is a feat worth the time.  You’ll love the results!  Put the milk in a different large bowl or pitcher that will hold at least 10 cups.  It will take about 1 hour or longer to fully strain. The strained Campari in the bowl should look crystal clear, perhaps with a few small curds settling at the bottom of the bowl. If the Campari is still a little cloudy, strain it through the raft of curds a second time. You can also try straining it through a coffee filter. Add more red food coloring to your clarified Campari, if you like. Some of the hue gets trapped in the discarded curds. Do you understand the chemistry behind this better than us? Please chime in in the comments!