Rather than grain, Bertha’s Revenge Irish Milk Gin is made from the distillation of alcoholic sweet whey, the liquid produced during cheese-making.
When you live in an Irish city that neighbors the world's oldest cow, who was also awarded not one but two Guinness records, a cow who birthed 39 calves in her 48 years on this planet, you better name your newly founded milk gin after her. Bertha was an overachieving Irish cow: She even managed to have been born on St. Patrick's Day, and also helped to raised thousands of dollars for cancer research with her cow-lebrity appearances at cattle fairs during her lifetime.
And now there is a gin named after her—a spicy Irish sup, the first of its kind, the grass-to-glass Bertha's Revenge Irish Milk Gin.
Banish all visions of gin cocktails with milk mixed into them, though. What makes Bertha's different from other gins is that a whey alcohol is used for the base spirit, whereas most gins are distilled from grain. Whey (sweet whey, not acid whey) is the liquid produced during cheese-making; when milk is curdled and then strained, the curds are then used to produce cheese.
"It was very important to us to make a gin using an Irish-produced spirit. Where an awful lot of gin makers now in the UK and Ireland would be importing the base spirit from France or mainland Europe, that didn't match our approach to farm to fork philosophy. We wanted the base spirit to be evocative of our terroir," owner-operator of Ballyvolane Guesthouse and co-founder of Bertha's Revenge, Justin Green, told me on the phone from the cowshed which houses the Bertha's Revenge in-house distillery. The distillery is on site at Ballyvolane, a fancy guesthouse which Justin's father previously ran as a dairy farm. Ballyvolane sources produce and foraged wild edibles for their kitchen from their own walled garden throughout the year, as well as keeping chickens and rare-breed pigs. The last four generations of the Green family have lived at Ballyvolane house, itself dating back to 1728.
In Ireland, whey was historically seen as a waste product that used to be fed to pigs, or spread on the land and disposed of, Green explained. "In fact, it used to be used in the petrochemical industry and the pharmaceutical industry, and entered the food chain about 15 years ago." Green added that local Cork dairy plant Carbery pioneered the development of a special yeast to ferment the milk sugars which naturally occur in sweet whey, and have been fermenting whey since the 1970s, providing well-known booze such as Bailey's with their fermented whey, and now Bertha's Revenge.
The initial whey-alcohol tip came directly from master distiller Charles Maxwell, during a visit Green and childhood friend/gin co-founder Antony Jackson undertook to the Thames distillery in London, whose family have been distilling gin since the 1680s.
"He said, 'Guys, you should check out the whey, it's absolutely fantastic quality and it's produced in Ireland,'" Green remembered. "'Ticks all the boxes as far as you're concerned.' So we left his office thinking, right—we're onto something."
The process for Bertha's Revenge Milk Gin begins at the local Carbery dairy plant, where the gin mash is made: first, the whey is brewed and yeast is added. Heat is applied initially to create the mash, and then the mash is distilled twice. Each time the mash is distilled, it brings up the ABV content, and refines the spirit further with each process. Ballyvolane then buys in the whey ethanol from Carbery at 96 percent alcohol.
Once the whey ethanol arrives at the cowshed distillery at Ballyvolane, it's poured into their 125-liter copper stills at a ratio of 1:1 with water (from a spring well on the farm, of course) to be distilled a third time. This is when the Bertha's Revenge mix of homegrown and locally foraged botanicals are added. They are now distilling approximately 800 liters per week at Ballyvolane.
"The well on the farm has been here as long as I have and I'm 47," Justin says, "So it's our own well water, which we maintain and test. It's really good quality, and there's no chlorine. If you were distilling gin in the city, you'd be plugged into the mains, and you'd have to use all sorts of filtration systems. There'd be quite high quantities of fluoride and chlorine in the water. Our water is as pure as you can get."
Green talked me through the main ingredients of Bertha's Revenge, which the team spent nine months perfecting.
"For gin to be gin, there has to be a predominance of juniper—it's all about the juniper," Green said. "The largest quantity of botanical going into any gin would be juniper, to give it that dry, pine-y, resinous flavour. Coriander seed gives the spicy and citrus notes. You have to have roots. Iris roots is another interesting one; it's the root of an Iris flower, it's a bit like salt and pepper—you wouldn't know that it's there, you can't really taste it, but if it's not there, it's missing something. It's also a binder—it makes all the other botanicals work together."
Ireland doesn't boast much of a production of citrus peels or juniper, so these are ingredients which they buy in. Several of Bertha's ingredients are foraged locally, however, to provide a unique Irish spiciness.
"We forage Alexanders locally, which is a little peppery black seed that forms in late August. Early September, they're still on the plant," Green said. "We've been out this time of year [in October] picking Alexanders and they give the nice high pepper notes. We also forage elderflower in May and dry the flowers to use them throughout the year. We forage sweet woodruff as well, which is a very delicate, star-shaped plant with green leaves and a delicate white flower, which gives almond and vanilla flavors."
For the delicate floral notes, those botanicals are suspended from the top of the still, so these are more vapour-infused. It's a slightly different style of distilling the botanicals, suspended from a little basket at the top of the still. This is to avoid a "cabbagey" taste, like overcooked tea, Green said.
Using whey for the base alcohol also delivers different results once you've raised the glass to your mouth. "It's not just that the whey is different, but the actual characteristics of the whey are very different. It brings a different mouthfeel," Green explained. "We hadn't initially set out to create a spicy gin, but we realized quite quickly that the quality of the whey is quite rich compared to grain spirit, and it carries the spices incredibly well."
Green suggests Bertha's Revenge is ideal for a negroni, gin and tonic, of course, or a White Lady—with Cointreau, egg white, and lemon juice—and also recommends trying it out as an after-dinner digestif, with just a splash of water and some ice. Your author tested out the latter version and can verify the extremely satisfactory supping sensation, though I forgot to add the water. (Firy—try it.) Don't try it in a Red Snapper, though, Green warned.
Green said that during their research phase, he learned that people have a real desire for knowledge for how things are made. They don't trust the big brands any more; they feel that the big brands tend to cheapen everything.
"When we talked to hairy hipster cocktail bartenders with tattoos, they wanted to feel the pain of the distiller," Green said. "They want to feel the passion. They rate what we're doing very highly because we're doing it all ourselves. You can taste the results."
The motivation behind creating an Irish milk gin was fueled by surviving tough times during the recession in Ireland after 2008.
"It is hard earning a crust in rural Ireland. We have a tiny population here, and we've tried lots of different things, but we had a really tough time in the recession," Green recalled. "We just felt if we can create something which has all the values of Ballyvolane House—farm-to-fork, and high-quality—we'll secure the future of Ballyvolane House in the long term."
Green went on to say, "Food in Ireland is really coming along now in leaps and bounds, and it's coming from the bottom up. Ireland has always had a bit of an inferiority complex when it comes to food. We always look to France and Italy, but we're surrounded by these incredible ingredients, and most of it gets exported around Europe. We should be complimenting our own ability to use them well—keep it simple, use really good ingredients, cook them with real flair. We have the ability to do that."
Going back to Bertha, Green said, "People might be a little bit put off by the milk factor, but just try it."