How to Make Oat water
Fermented oat water is a creamy, mildly tangy probiotic drink made by fermenting oats in water. It has a pleasant, slightly sweet flavor and smooth texture.
Category: Beverages · Method: Lactic Acid · Time: 2-5d · Difficulty: 1/5 · Yield: varies · Temp: 20-24°C
History
Fermented grain beverages have ancient roots in many cultures. Oat-based drinks are traditional in parts of Latin America and have gained popularity as dairy alternatives.
Ingredients
- 1 cup Rolled oats — Old-fashioned or steel-cut; avoid instant oats which are too starchy.
- 4 cups Water — Must be cold and filtered to prevent starch gelatinization.
- 2 tbsp Starter Culture — Fresh whey, raw sauerkraut juice, or 1/2 cup of a previous batch (backslop) to ensure LAC dominance.
- 1/4 tsp Sea salt — Essential for inhibiting spoilage bacteria during the initial fermentation phase.
- 1 tbsp Sugar or Maple Syrup — Provides immediate fuel for the lactic acid bacteria.
- 1 Cinnamon stick — Optional
Equipment
- Glass jar
- Fine strainer or nut milk bag
- Bottles
- Blender
Instructions
Cold extraction
Combine oats and cold filtered water. Pulse in a blender for only 15-20 seconds. Do not over-blend or use warm water, as this releases excess starches that cause a 'slimy' or 'ropy' texture.
Time: 5 min
Tip: Using ice-cold water helps keep the oat starches stable.
Strain and Inoculate
Strain the mixture through a fine-mesh sieve or nut milk bag into a clean glass jar. Stir in the salt, sugar, and your chosen starter culture (whey or kraut juice).
Time: 10 min
Primary Fermentation
Cover the glass jar with a breathable cloth (cheesecloth or coffee filter) secured with a rubber band. This allows CO2 to escape while protecting the liquid from contaminants and fruit flies. Place in a dark spot at 20-24°C.
Time: 2-5 days
Tip: Taste daily after 48 hours. It is ready when it smells clean and slightly acidic (pH < 4.5).
Bottle and Chill
Once the desired tanginess is reached, remove the cinnamon stick, seal with an airtight lid, and move to the refrigerator to slow fermentation.
Time: 5 min
Fermentation Timeline
- Day 1: Start — Oat flavors begin developing.
- Day 2-3: Active — Light tang develops, slightly fizzy.
- Day 4-5: Ready — Creamy, tangy oat beverage.
Signs of Success & Spoilage
Good signs
- Creamy texture
- Mild tang
- Oaty aroma
- Light bubbles
Warning signs
- Slimy
- Off smell
- Bitter taste
- Mold
Troubleshooting
- Slimy or 'ropy' texture
- Cause: Over-blending, using warm water, or lack of competitive starter culture. Solution: Ensure water is cold, blend minimally, and always use a starter to quickly lower the pH.
- Mold on surface
- Cause: Contaminated equipment or exposure to fruit flies. Solution: Discard the batch. Ensure the fermentation vessel is sanitized and the breathable cover is tightly secured.
- Putrid or 'cheesy' smell
- Cause: Spoilage bacteria (butyric acid) took hold before LAC could dominate. Solution: Increase the amount of starter culture and ensure salt is included in the recipe.
Storage
Refrigerate Keeps 1 week. Shake before using as it separates.
Health Benefits
- Probiotics
- Beta-glucan
- Fiber
- B vitamins
- Low fat
Serving Suggestions
- Breakfast drink
- Smoothie base
- Coffee creamer
- Cereal milk
- Baking ingredient