There are a few signs that summer has truly arrived: the days stretch longer, the hedgerows burst into life and, for a few precious weeks, the air carries the unmistakable scent of elderflower.
Every year, I look forward to this fleeting moment. Elder trees suddenly appear everywhere, covered in delicate cream-coloured blossoms that smell like honey, citrus and warm sunshine.
Making elderflower cordial has become an early summer ritual in my kitchen. It’s simple, delicious and captures the essence of the season in a bottle.
This year, though, something unexpected happened. Or perhaps I should say something deliciously expected.
Oops, I left my cordial in the bottle a little too long and it fermented, turning into elderflower champagne.
Why elderflower?
For generations, elderflower has been used in traditional food and herbal practices across Europe.
Beyond its beautiful flavour, elderflower is traditionally associated with supporting:
- The immune system
- Seasonal allergies and hay fever symptoms
- Healthy digestion
- Cooling the body during warmer months
- Gentle relaxation and wellbeing
The flowers contain antioxidants and plant compounds including flavonoids, which contribute to their traditional use.
From an Ayurvedic perspective, elderflower’s light and cooling qualities make it particularly welcome during the heat of summer.
Capturing summer in a bottle
Traditional elderflower cordial combines fresh elderflower heads with water, citrus, sugar and a little patience.
Lemon is an essential ingredient, adding brightness, flavour and acidity. Many recipes also include citric acid, which helps preserve the cordial, enhances the fresh citrus notes and creates the acidic environment needed for safe storage.
The sugar preserves the flowers’ delicate aromas, while the combination of lemon and citric acid balances the sweetness and helps the cordial keep for longer.
Mixed with sparkling water, poured over ice or added to desserts, cordial is one of the simplest ways to enjoy the short elderflower season long after the blossoms have disappeared.
Unless, of course, you accidentally forget about it.
So, how did my cordial become champagne?
The answer lies in wild yeast.
Elderflower blossoms naturally carry tiny amounts of wild yeast on their surface. These microscopic organisms are invisible to the eye but are present throughout nature.
When yeast encounters sugar in the right conditions, it begins to feed.
As it consumes the sugar, it produces two things:
- Carbon dioxide
- Alcohol
Even though lemon juice and citric acid increase the acidity of the cordial, wild yeasts can still thrive if enough sugar remains and the conditions are favourable.
If your cordial is stored in a sealed bottle, the carbon dioxide has nowhere to go. It dissolves into the liquid, creating bubbles and turning your cordial into a naturally sparkling drink.
In other words, fermentation happened. It’s the same process used to make bread, kombucha, beer and wine.
How much alcohol does elderflower champagne contain?
The alcohol content depends on several factors:
- The amount of sugar used
- The temperature during fermentation
- How long the drink ferments
- How active the wild yeast is
- The acidity of the cordial, including the amount of lemon juice and citric acid used
Most homemade elderflower champagne falls somewhere between 0.5% and 3% alcohol by volume (ABV).
A short fermentation of a few days usually produces a lightly sparkling drink with relatively low alcohol levels.
Left for several weeks, particularly in warm weather, the alcohol content can increase.
Without measuring sugar levels before and after fermentation using a hydrometer, it’s impossible to know the exact alcohol content.
If you’re serving elderflower champagne to children, pregnant women or anyone avoiding alcohol, it’s safest to assume that it contains some alcohol.
A few words of caution
Fermentation is fascinating, but it deserves respect. Always use clean, sterilised bottles and equipment, and never fill bottles completely to the top.
As pressure builds inside sealed bottles, there is a risk of exploding glass.
Flip-top bottles should be “burped” regularly during active fermentation by carefully opening them to release excess pressure. You can use plastic screw top bottles for easier burping.
I like using the empty bottles of mineral water or sparking water. Be warned that if you don’t watch for the gas formation and let it out, even the bottom of the bottle can expand and tumble over!
If the drink develops mould, an unpleasant smell or signs of spoilage, discard it.
A healthy fermentation should smell fresh, floral, citrusy and pleasantly yeasty.
The joy of happy accidents
One of the things I love most about cooking from scratch is that it invites curiosity.
Sometimes we follow a recipe perfectly. Sometimes nature has other plans.
Leaving my elderflower cordial in the bottle a little too long reminded me that food is alive. Wild yeasts, bacteria and time can transform simple ingredients into something entirely new.
So if your cordial unexpectedly becomes champagne, don’t panic.
You haven’t failed. You’ve simply discovered another way to bottle summer.
Wishing you a rewarding time outdoors.