“Vinegar's the Zamboni for the tongue." -Kelley Slagle
Acid, in cooking, is used by savory and pastry chefs alike to punch up or brighten a dish. Often the little hint of lemon, lime or vinegar is hidden from true view, lurking just under the surface. You might not recognize that it is even there, but its absence would be noticed.
In drink making, bartenders also search for acid to punch up or balance cocktails: without the refreshing hit of lemon or lime in your sour or margarita, you would just have sweetened flavored booze, and that would be no fun at all.
What acid can also do, in liquids and in solids, is contribute the elusive “craveability,” that thing that is in a dish or a drink that makes you want to have another bite or order another round.
As bartenders though, modern tradition limits our acidic choices to the ubiquitous lemons, limes and grapefruit. Occasionally, you will see a more exotic citrus—perhaps a Mexican Sour Orange or a Calamansi from the Philippines—appear in a cocktail, but the choice is usually limited to the basic citrus varieties, and when you are mixing and drinking cocktails daily, it can get, frankly, a little monotone.
There are historical choices though, that provide other options to expand the palette of sour in our drinks. There is, of course, vermouth, which has an acidic wine as its base and helps to balance out the classic Martini and Manhattan. There is also Acid Phosphate, that old ingredient of the soda fountain that has been resurrected from the dead and is available again. It has roughly the same acidity as lime juice, but is completely neutral in flavor, and allows a good bartender or soda jerk to balance out sweet without changing flavor.
But the most exciting of the options is vinegar, most usually in the form of an early American innovation in preservation called a Shrub.
The Linguistics & the History of the Thing
In 16th and 17th Century England, shrubs were a different, non-vinegar beverage. Derived from the medicinal cordials first produced in the 15th century, they were a highly concentrated mixture of fruit and alcohol and frequently a lot of sugar, and they were used as sort of a pre-made drink mixer in punches or added to liquor barrels that smugglers had sunk in the English Channel to avoid capture. Later, the retrieved barrels, with the booze inside affected by seawater, would be masked with Shrubs and sold. Fancier versions were produced around the holidays, until the whole thing fell out of fashion in the 1800s.
Drinking vinegars of different sorts crop up all over the world, but “Shrub” most likely is an Anglicization of either the Arabic sharab, for syrup or the Hindi sharbat, an aromatic syrup of fruit, herb and flower extracts that is also probably the root of sherbet as well. And in 18th Century America, a shrub was decidedly vinegar based.
Picture, for a moment, a time before easy rail shipping and refrigeration. The economy is largely agrarian and what is consumed is what is grown, harvested or foraged locally. The climate is variable—dormant, cold winters followed by a growing season in the spring and summer that fades into autumn before going dormant again.
Your farm grows wheat and corn to feed you and your animals; maybe you have some apple or peach trees and a small vegetable garden filled largely with root vegetables you can store in the cellar after harvest. Perhaps a neighbor has pears and grows some barley or oats. Berries grow wild along the hedges and fence rows, and there are cherry trees nearby. For a few brief weeks in the summer there is a bounty of fresh fruits, and you and your family go forth and harvest it all.
What you cannot eat right away must, somehow, be saved. You can allow the juice of the fruit, in particular, to ferment and bottle it as a kind of wine or vinegar. If you are lucky, you or someone nearby has a still and you can make liquor from the fruit wines as well. You can dry and mill the grain and store it in silos for animals or in sacks for your family. Maybe some beer is made from that grain too, and perhaps, from that beer, some whiskey is distilled.
But in those bushels of fruit there is another option. Citrus is a rich man’s luxury, from the far corners of the globe, but if you can add sugar and vinegar to your fruit you can create a shelf stable syrup that can be added to water to flavor it (and potentially kill any harmful bugs lurking in it). The process is simple, requiring only a little time, and the resulting syrup is the essence of fresh summer fruit, tart and refreshing with a mild sweetness. Oh, and as someone surely figured out quite quickly, it also mixes quite well with your hooch.
A Brief How-To
The easiest and least fussy way to produce a shrub is probably the most historically accurate as well. Grab a quantity of the ripest fruit you can find. Look for the berries that are almost ready to go bad, the stuff that you would otherwise waste. Roughly chop that fruit, weigh it and toss it in a bowl. Now take an equal quantity of sugar and dump it on top of the fruit and cover with a cloth (or Saran Wrap). Walk away for a few hours or a couple of days. Through a process called hydrophilia, sugar will draw out the liquid from inside the fruit and create a rich, fruit flavored syrup in your bowl. You can come by and stir this mixture every once in a while, but it’s not necessary. You can store it in the fridge if you’re fearful, but it will work on the countertop just fine (and faster).
When you think you have extracted all the liquid you’re going to get (if you start with a cup of sugar and a cup of fruit, you should have about a cup of syrup), toss an equal quantity of vinegar into the bowl, stir the whole thing up to incorporate any sugar that is lurking on the bottom, strain out the solids and bottle the liquid in a sealable jar or bottle.
Done, and you can consume it right away, though it will mellow and evolve very pleasantly over time.
This process is called, by modern practitioners of the shrub, “The Cold Process.” The resulting syrup is snappy and tart but lush with the flavor of fresh, extremely ripe fruit. And it is delicious mixed with soda water to make a non-alcoholic, grown up sparkler, but depending on your fruit and vinegar choices, it will also mix with any number of spirits to make surprising cocktails.
What Kind of Fruit?
What kind do you have? What kind do you love? Go to town.
If it contains fructose, it can be made into a shrub. Vegetables will also work—a tomato shrub can be a surprising and delicious addition to a Bloody Mary, and an Apple-Ginger Shrub (which would technically be called a Switchel do to the inclusion of ginger), mixes exceedingly well with a dry sherry and a couple of dashes of bitters to form a light aperitif.
A Brief Note on Acidity
Although limes can vary widely in acid level, they commonly have a pH of 2.0 - 2.35. Lemon juice is also in that ballpark, and vinegar, despite its generally being perceived as more sour than citrus, is usually less acidic than either of the citrus fruits, coming in at a pH of roughly 3 (depending on variety of course), the same pH as Coca Cola.
In the shrub preparation, the sucrose from the sugar and the fructose from the fruit combine with the acidity of the vinegar to smooth out the rough edges, and that the resulting syrup, while reminiscent of vinegar, is not remotely similar to salad dressings. It is however, more rich and boldly flavored than anything that can be squeezed from a citrus fruit and must be used with a lighter hand when mixing.
Hot Process and Cheater Shrubs
There are those who will argue that a Shrub can be made on the stove top by simply combining an equal by weight measure of fruit, sugar and vinegar in a saucepan, bringing the whole thing to a boil, dissolving the sugar and simmering until the fruit is soft and mushy with its flavor leached into the resulting syrup.
This does work, but it is not nearly as bright in flavor as the Cold Process method. Instead the syrup tastes “cooked” or jam-like instead of being redolent of fresh summer fruit. It also dirties a pot and the syrup is more sharply vinegar flavored. For certain harder fruits or vegetables, it is certainly an option—carrot is one that comes to mind—but for your berries and most stone fruits, the cold process will be superior.
Shrubs are shelf stable. You don’t have to refrigerate them (though it won’t hurt them either), but they do mellow rather nicely over time and the three ingredients come into better harmony, and the science behind that process is totally awesome.
The natural yeasts present in the air and on the fruit convert some of the residual sugar in the mixture into alcohol. While that’s happening, the acetobacter (a naturally occurring bacteria) turns the alcohol into more vinegar, until, eventually, an equilibrium is reached when the bacteria-induced pH change (the creation of more vinegar) stalls out the yeast’s ability to ferment sugars, which then in turn chokes out the bacteria’s vinegar producing pathway.
That’s a technical way of saying that within a week or two, your shrub will be mellower and more delicious than it was when it was first produced. It also doesn’t happen nearly as much in the hot process method as the heat destroys most of the yeast.
Your Choice of Vinegar
Shrub devotees often claim that Apple Cider Vinegar is the go to choice for shrub making and it does make a nice shrub indeed. Red Wine Vinegar is very nice with complimentary fruits and Champagne Vinegar is usually terrific with anything.
Generally plain white vinegar is too sharp and powerful to be used and should be avoided. Aged Balsamic Vinegar, because of its powerful flavor, can be difficult to work with in this context, but White Balsamic, particularly with strawberries, is outrageously delicious.
Think in terms of complementary flavors; consult The Flavor Bible (the single best resource I own for creating cocktails and cooking) for guidance if you are uncertain and experiment.
Using the Things for Drinking
One of the easiest way to use a Shrub is to toss about half an ounce of the stuff into a tall glass with a shot of a complementary spirit (how about peach shrub and Bourbon?), and top the whole thing off with soda water and maybe a dash of bitters.
But how you use a shrub will be dependent on your base materials (fruit and vinegar) and the sweet/acid balance of your finished syrups, which can vary considerably depending on the ripeness of the fruit, the maceration time and the choice of vinegar, but a general recipe would look something like this:
1 ½ - 2 parts base spirit
1 part complementarily flavored liqueur
½ part shrub
2-4 dashes complimentary flavored bitters.
Stir it up with ice, strain it into a chilled cocktail glass or over ice, garnish with something that makes sense, and enjoy.
A Few Quick Final Words
Shrubs are useful—and interesting—in the bar because they allow a bartender to get a balanced drink with a wide variety of flavors, instead of the more usual citrus forward cocktails.
You are only limited in the flavors you can create by the fruit and vinegars available to you. You can combine fruits to make complex flavors, you can add herbs or spices to the maceration period to lend different notes to the finished product and you can mix and match with vinegars—coconut vinegar intrigues for use in Tiki Drinks, does it not?
1 cup tightly packed rough diced ripe strawberries, hulled
½ cup diced rhubarb
1 cup sugar
1 cup White Balsamic Vinegar
Combine the sugar, rhubarb and strawberries in a bowl large enough to hold them with a couple of inches space to spare and stir until the fruit is coated with the sugar. Cover the bowl with cling wrap and store in the refrigerator for a minimum of three hours and up to three days, stirring every so often if you wish.
Remove from refrigerator, stir in the vinegar, making sure all sugar is dissolved. Strain out solids, bottle and store in pantry or refrigerator.
Peach and Ginger Shrub
1 cup tightly packed rough diced ripe peaches, pitted.
¼ tsp fresh grated ginger
1 cup sugar
1 cup Champagne Vinegar
Combine the sugar, peaches and ginger in a bowl large enough to hold them with a couple of inches space to spare and stir until the fruit is coated with the sugar. Cover with cling wrap and store in refrigerator for a minimum of three hours and up to three days, stirring every so often if you wish. Remove from refrigerator, stir in the vinegar, making sure all sugar is dissolved. Strain out solids, bottle and store in pantry or refrigerator.
Enjoy (and tell me what you’re making and how you’re using it).