What is the white film or bubbles on top of your ferment? Learn how to tell if it's dangerous mold or harmless kahm yeast, and what action to take.
1 Answer
The white film or bubbles are likely kahm yeast, a harmless byproduct of fermentation. You can usually scrape it off the surface and continue fermenting.
Detailed Explanation:
Distinguishing between kahm yeast and mold is crucial for safe fermentation. Kahm yeast appears as a white or off-white film, often with a wrinkled or bubbly texture. It's generally harmless and develops when wild yeasts interact with the surface of your ferment. Mold, on the other hand, typically has a fuzzy or velvety appearance and can be various colors, including green, blue, black, or pink. If you see mold, it's best to discard the entire batch, as it can produce toxins.To determine if it's kahm yeast, observe its appearance closely. Kahm yeast usually forms on the surface exposed to air. If it's just a thin, white film, it's likely kahm yeast. You can carefully scrape it off the surface using a clean spoon or utensil. Ensure you remove it completely to prevent it from affecting the flavor of your ferment. After removing the kahm yeast, monitor your ferment closely for any signs of mold. If you're unsure, it's always better to err on the side of caution and discard the batch. Maintaining a clean environment and ensuring your vegetables are fully submerged in the brine can help prevent kahm yeast from forming in the first place.
Pro Tip:
To prevent kahm yeast, ensure your ferment is fully submerged under the brine. Use a weight, such as a glass weight or a clean ziplock bag filled with brine, to keep the vegetables submerged and minimize air exposure.