Essential Food Preservation Techniques

Lucy Brazier shares her experience of learning techniques to preserve food during Rachel de Thample’s Seasonal Fermentation course.

Rachel de Thample is an expert when it comes to fermentation—she’s a master of making fermented foods and pushing the boundaries of flavour and technique. On a frosty morning this week, with River Cottage HQ nestled beneath the valley mist, I joined her and the team in our 18th-century barn for a sneak peek at her Seasonal Fermentation day.

We began the day with freshly brewed coffee and buckwheat kefir blinis, as Rachel introduced us to the basics of fermenting foods. She started with her honey-fermented clementine marmalade, a delicious nod to ancient Greek and Roman methods of preservation, such as covering quince in honey. The beauty of fermentation is its versatility—Rachel suggested swapping clementines for seasonal ingredients like rhubarb, cherries, or even rosehips to make fermented foods using the same technique.

When it comes to fermentation, Rachel emphasised three main factors: time, temperature, and trusting your taste buds. “It’s about mastering ratios and techniques to preserve food, rather than sticking strictly to recipes,” she said, encouraging us to experiment. We made our own ‘krautchi’—a mix of sauerkraut’s salt-massaged cabbage and kimchi’s garlic and chilli. In another jar, we layered apple rings with ginger and thyme, then covered them in brine. In just a week, these fermented foods would be ready to enjoy with roast pork or as a cheeseboard addition.

The day was packed with inspiring tasters: sourdough cardamom buns with cranberries and rose petals, elderberry and Earl Grey kombucha, and a vibrant board of lacto-fermented fruits and vegetables. Rachel’s fermentation techniques truly opened our eyes to the endless ways we can preserve food. From fermented apples and limes to a surprising parsnip and quince combination, her creativity shone through.

Rachel’s generosity in sharing her expertise made the experience even more enriching. I left with jars of my own ferments and the beginnings of a ginger beer ‘bug’—a simple technique to make fermented drinks at home. With clear instructions to follow over the next few days, I felt empowered to continue exploring how to make fermented foods and try new preservation techniques. Join River Cottage on their next Fermentation course with Rachel.