While travelling to Russia, Catherine the Great stopped in Riga for a few days' respite. However, shortly after her arrival, she became extremely ill. There are two theories why. The first is simply that she developed a stomach infection such as typhus. Records show the disease was around at the time. The other notion is tainted with treachery. Some speculate she was poisoned. This was a commanding woman creating vast change across an empire and a number of Russian nobles were, shall we say, unimpressed.
Her English physician was out of ideas. The Empress' life was on the edge and it did not bode well for Latvia if she died in their care. It was a long shot, but Kunze and his ambitiously advertised Miracle Elixir were called for.
"They thought: 'He's probably a charlatan, but let's give him a try. If he fails, we know who to blame. If he succeeds, it's a win for us.' Well, sometimes miracles happen," Valters says, grinning.
Catherine the Great rose from her deathbed espousing Kunze's balsam as a healing wonder. Its popularity throughout Europe was sensational.
Understandably, many counterfeits invaded the market, so the Empress gave Kunze exclusive rights for 50 years to produce the tincture. Its formula became a closely guarded secret. Even now, among 600-plus employees at Latvijas Balzams, only three people know it completely - the liquor master and two apprentices. But here's where the story takes a twist.
During World War II, the recipe was lost.
Many who worked at the factory fled to other countries and production came to a firm halt. After the war Latvia's people started returning. One technologist in particular held intimate knowledge of how the balsam was prepared. Maiga Podracniece's information guaranteed its renewed manufacture. She passed away in Riga in December, aged 87.
More than 2 million bottles are produced yearly and exported to 30 countries, from just four Austrian oak barrels. Chatting with Latvians, you'd think the ingredients are still top secret. Not so.
Seventeen of the 24 components are herbs, roots, berries and buds. The remaining seven contribute to its 45 per cent strength, including burned sugar, which gives the balsam its brooding pallor. All natural, no preservatives or colouring. The mystery of the tonic is in its making. "Buds and flowers get put in in a specific order. The quantities are being measured very, very precisely." The moon's phases are also considered. It's all about magnetics and gravity's pull affecting minerals in the water used. Latvijas Balzams has a private well "several hundred metres deep" outside Riga. This way it's not depleting city networks and quality control is easier.
Combined, the first 17 ingredients mature in the barrels for four weeks. The outcome is a potent brew, used for centuries as a homeopathic remedy. Even now, if an employee is feeling "under the weather", they come to the liquor master for a shot of balsam essence. A Latvian friend told me her grandmother swore by the potion, faithfully consuming a teaspoonful every morning. She lived to her mid-80s.
New Zealand has around 10,000 Latvian migrants, but their heritage balsam is not yet available in stores. The travesty is that Australia has fewer Latvians than we do but you can buy Riga Black Balsam there. In other words, export is costly. Valters acknowledges: "It's produced in a handmade manner and uses damn expensive bottles."
The bottles haven't changed for more than 200 years.
A clay amphora houses the beverage; a porous, ecological container which allows the liquor to breathe and protects it from the elements.
And the taste? Anywhere between a palatable cough medicine to liquid tar. "It's complex. It has an inner strength. It has backbone. It has substance."
You can't argue with that, especially when it's a drink that's outlasted four wars, five political systems and 13 generations.
Emily Kernot is a freelance journalist travelling in Europe. emilykernot.blogspot.com