Knowledge Base

Brown Rice Vinegar

BRV

Microbial culture · Master Cho · KNF

Rice wine turned to vinegar by acetic-acid bacteria — a mild acid that sterilizes, thickens leaves, and unlocks calcium.

All stages
Moderate to make
14–30 days ferment
1:500 dilution
acetic-acid, calcium-absorption, sterilization supplied
＋ Start a batch from this recipe

Dilution calculator

Dilution 1:500

Enter a water volume to see how much to add.

Ingredients

  • Rice wine (Makgeolli-style)1 batch
  • Acetic-acid bacteriawild from the air, no starter needed

How to make it

  1. Step 1

    Prepare rice wine the same way as Makgeolli (Korean rice wine).

  2. Step 2

    Leave the ripe Makgeolli as it is — acetic-acid bacteria turn it to vinegar on their own.

  3. Step 3

    Keep it loosely covered so the acetic-acid bacteria get the air they need.

  4. Step 4

    Ferment until soured into vinegar (a 15-day fermented toddy also turns to vinegar).

  5. Step 5

    Strain off the finished brown rice vinegar.

  6. Step 6

    Drop eggshells into BRV for water-soluble calcium, or bones for calcium phosphate.

  7. Step 7

    Store cool and shaded; dilute 1:500 to spray.

What it is

BRV is brown rice wine that acetic-acid bacteria have soured into vinegar. Though acidic itself, it becomes alkaline once absorbed by plants, livestock or people, and it carries phytic acid, amino acids and organic acids. On crops it sterilizes, thickens leaves into a waxy protective layer, and raises calcium absorption. It is the acid you use to make WCA (water-soluble calcium) and WCP (water-soluble calcium phosphate).

On the Nutritive Cycle: BRV is an all-stages backbone. In low concentration it aids vegetative leaf growth; in high concentration it accelerates reproductive growth; and it goes into IMO-3, IMO-4, enriched compost, soil, seed and seedling treatments.

When to use it

  • Sterilizing — 1:500 at the juvenile-leaf stage; 1:200–1:300 at the adult-leaf stage.
  • With water-soluble calcium — BRV maximizes calcium's effect.
  • Making calcium inputs — eggshells in BRV for WCA; animal/fish bones for WCP.
  • All treatments — soil groundwork, seed and seedling, and every growth period.

Materials

  • Rice wine made the Makgeolli (Korean rice wine) way
  • A loosely covered vessel and open air — wild acetic-acid bacteria do the rest
  • (Alternative: 15-day fermented toddy will also turn to vinegar)

How to make it

  1. Make the wine. Prepare rice wine exactly as for Makgeolli.
  2. Let it sour. Leave the ripe Makgeolli as it is; acetic-acid bacteria convert it to vinegar.
  3. Give it air. Keep it loosely covered so the bacteria can breathe.
  4. Wait. Ferment until fully soured into vinegar.
  5. Strain and use. Dilute 1:500 to spray, or steep eggshells/bones to make WCA and WCP.

Signs it worked / troubleshooting

  • ✅ Good: sharp, clean vinegar smell and taste.
  • ⚠️ Still sweet or weakly sour = not finished → give the acetic bacteria more air and time.
  • 🚫 Slimy or foul rot = spoiled → discard and restart.

How to store

Keep cool and shaded in a covered vessel. Dilute only when you're ready to spray.

Related

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