Feijoa Water Kefir (Second Ferment)

When we were drowning in feijoas back in Daylesford—courtesy of generous locals and Sue Dennet's incredible Melliodora harvest—we made feijoa hot sauce and this: feijoa water kefir. It was one of those happy accidents that became a favourite. We used frozen feijoa purée (blended with skin on) or fresh fruit, paired it with fresh ginger, bottled it for a second ferment, and ended up with a fizzy, tropical, slightly funky drink that tasted quite like musk sticks, and... well nowhere else I'd every had this before. 

Water kefir is naturally effervescent, probiotic-rich, and less sweet than kombucha. The feijoas add natural sugars for carbonation, a beautiful pale peachy-green colour, and that distinctive floral flavour. This is a second ferment recipe, which means you'll need to have already completed your first ferment of water kefir, or use our first ferment water kefir pouch so you can simply add the fruit to that without the work of looking after the grains.

Makes approximately 1 litre

Feijoa-Ginger Water Kefir (Base Recipe)

Ingredients:

• 1 litre strained water kefir (first ferment complete)
• 150-200g ripe feijoas (3-4 medium fruits)
• 20g fresh ginger, thinly sliced or grated
• Optional: 1 tablespoon extra sugar (for more carbonation)

Method:

1. Prepare the feijoas: If using fresh feijoas, wash them well, remove the dried flower end, and blend whole (peel and all) until smooth. If using frozen feijoa purée, thaw it first. You want about 150-200g of purée.
2. Combine: In a clean jug, mix the strained water kefir with the feijoa purée and ginger. Stir well to distribute evenly.
3. Bottle: Pour into clean swing-top bottles or bottles with tight-sealing lids, leaving about 3-4cm of headspace at the top. Divide the ginger pieces between bottles.
4. Second ferment: Seal the bottles tightly and leave at room temperature (18-24°C) for 24-48 hours. The natural sugars in the feijoas will feed the remaining yeasts and bacteria, creating carbonation.
5. Burp daily: Open the bottles once a day to release pressure (this is called "burping"). You'll hear a hiss of CO2 escaping. This prevents over-carbonation and potential bottle explosions.
6. Taste and refrigerate: After 24-48 hours, taste your kefir. It should be lightly fizzy, aromatic, and balanced between sweet and tart. When you're happy with the flavour and carbonation, move to the refrigerator. Cold storage stops fermentation.
7. Strain and serve: Pour through a fine-mesh strainer into glasses (to catch ginger pieces and feijoa pulp), or serve as-is if you don't mind texture. Serve chilled over ice.

Alternative Feijoa Flavour Combinations:

Feijoa-Lime-Mint:

• 150g feijoa purée
• Juice and zest of 1 lime
• Small handful of fresh mint leaves, bruised
• Fresh, herbaceous, tropical

Feijoa-Vanilla:

• 150g feijoa purée
• ½ vanilla bean, split and scraped (or ½ teaspoon vanilla extract)
• Aromatic, creamy, subtly sweet

Feijoa-Passionfruit:

• 100g feijoa purée
• Pulp of 2-3 passionfruit
• Intensely tropical, tart, complex

Feijoa-Lemongrass:

• 150g feijoa purée
• 1 stalk lemongrass, bruised and roughly chopped
• Citrusy, aromatic, Southeast Asian vibes

Feijoa-Apple-Ginger:

• 100g feijoa purée
• 100ml fresh apple juice (or 1 grated apple)
• 15g fresh ginger, sliced
• Mellow, balanced, autumnal

Notes:

• Carbonation safety: Water kefir can become highly carbonated during second ferment. Always burp bottles daily and use bottles designed for pressure (swing-top bottles or thick glass). Never use thin glass or plastic bottles not rated for carbonation.
• Fermentation time: Warmer temperatures = faster fermentation and more carbonation. In summer, 24 hours might be enough. In winter, you may need 48 hours or longer.
• Sweetness: If your kefir tastes too tart after the second ferment, you can add a touch of honey or sugar when serving. Don't add it during fermentation unless you want very fizzy kefir.
• Using the peel: Just like we did with the hot sauce, blending feijoas whole (peel on) works beautifully here. The peel adds tannins and complexity without bitterness.
• Freezing feijoa purée: Blend and freeze feijoas in 150-200g portions so you can make this kefir year-round, even when feijoas aren't in season.
• Straining vs. not straining: Some people love the texture of fruit pulp in their kefir. Others prefer it crystal clear. Do what makes you happy.

Why This Works

Feijoas are naturally high in sugars, which feed the beneficial bacteria and yeasts during the second ferment, creating excellent carbonation. Their aromatic, tropical flavour pairs beautifully with water kefir's mild tanginess. The ginger adds warmth and spice, cutting through the sweetness and adding digestive benefits.

This is a drink that tastes like autumn in Australia—fleeting, special, and worth making in bulk while you can. If you've got frozen feijoa purée stashed in your freezer, you can make this all year long and remember that brief, generous feijoa season whenever you need a little taste of it.