Spicy Fermented Mustard
Fermenting mustard enhances its flavour complexity, improves digestibility, and adds natural probiotics that support gut health and immunity. This mustard is super easy to make and has a depth of flavour you won’t find in store-bought varieties!
Takes 6 days 20 minutes
Serves 20
Ingredients
- 200 g yellow mustard seeds
- 50 g brown mustard seeds
- 1 fresh red chili or ½ tsp dried chili flakes, adjust to taste (approx. 15-20g)
- ¼ garlic bulb approx. 15g
- ½ small lime approx. 25g
- 500 ml filtered water for the brine
- 2 tsp 10g sea salt (non-iodized)
- 1 tbsp maple syrup or honey optional, for balance
- 50 ml reserved fermented brine for adjusting consistency after blending
- 4 tbsp apple cider vinegar optional, for extra tang after fermentation
Instructions
Prepare the Brine & Ferment the Mustard Seeds
- Dissolve 10g sea salt into 500ml filtered water to create a 2% brine solution.
- Place the yellow and brown mustard seeds in a sterilized jar.
- Add the chopped chili, ½ lime and minced garlic (if using) on top of the mustard seeds.
- Pour the brine over the mustard seeds, chillies, lime and garlic, ensuring they are all fully submerged.
- Weigh the seeds down with a clean glass to keep them submerged.
- Cover loosely with a lid or cloth and let it ferment at room temperature (18-22°C) for 5-7 days.
- Check daily for bubbles and a tangy aroma.
Blend & Adjust
- Drain the fermented mustard seeds, reserving the brine.
- Blend the seeds with 2 tbsp of reserved brine and add more until you reach your desired texture. Blend for longer if you want a smooth homogenous mustard or for less time if you want a chunky wholegrain mustard.
- Stir in maple syrup and apple cider vinegar for balance and ensure to season to taste adding more salt or vinegar till you reach your desired taste.
Store & Age for Flavor Development
- Transfer the mustard to a clean, sterilized jar.
- Store in the fridge, where it will continue to develop flavor over time.
- For best taste, let it mature for 1-2 weeks before using.
Notes
Why Ferment Mustard?
✅ Enhanced Flavor Complexity
- Fermentation mellows bitterness and creates a deeper, umami-rich mustard with tangy, slightly funky notes.
- Natural lactic acid bacteria (LAB) create a subtle sourness that complements the mustard’s heat.
✅ Improved Digestibility
- Soaking and fermenting mustard seeds can reduce antinutrients, making the nutrients more bioavailable.
- It can also reduce mustard’s naturally strong heat, making it smoother.
✅ Probiotic Benefits
- If fermented with lactic acid bacteria (like those from sauerkraut or whey), it can contain gut-friendly probiotics.
✅ Natural Preservation
- Fermentation naturally acidifies the mustard, helping it last longer without relying solely on vinegar.
