Maintaining the right temperature and selecting an ideal location for your kombucha brewing process are crucial for successful fermentation. Both temperature and environment directly impact the speed, flavour and overall quality of your kombucha. This guide will help you navigate the best practices for temperature control and location selection during both first fermentation (F1) and second fermentation (F2). 

Temperature Control 

Why Temperature Matters 

Temperature plays a key role in the fermentation process. It affects how fast or slow your kombucha ferments and how the bacteria and yeast in your SCOBY work to acidify the brew. The ideal temperature for both first and second fermentation is mid- to high-20s°C (24-27°C). However, kombucha will still ferment within the broader range of 18-29°C, though with some adjustments in timing: 

  • Cooler Temperatures (18-21°C): Fermentation will take longer, and your brew may take more time to develop acidity. 
  • Warmer Temperatures (26-30°C): Fermentation speeds up, causing your brew to acidify faster. 

Temperature Monitoring: Using Temperature Strips 

An easy and affordable way to monitor the temperature of your brew is by using temperature strips. These adhesive strips can be placed on the outside of your brewing vessel and give you a quick reading of the temperature. 

While not perfectly precise, they are effective enough for homebrewing and can help you avoid issues related to extreme temperatures. If the strips are unclear, rubbing your hand along the strip may reactivate it and give a more accurate reading.  

Managing Low Temperatures 

In colder weather, your kombucha may take longer to ferment. To help speed up the process and avoid issues like mould or slow acidification, try these tips: 

  1. Use Extra Starter Tea: Doubling the amount of starter tea can help kickstart the fermentation and acidify the brew faster, making it less susceptible to mould. 
  2. Wrap with String Lights: Wrapping holiday string lights around your vessel can gently warm it. Make sure to distribute the heat evenly by wrapping the lights around the entire vessel. 
  3. Keep Near a Heater: Place your brew near a warm spot in your home, such as near a heater or furnace, but avoid direct heat exposure. 
  4. Be Patient: Cooler temperatures will naturally slow down fermentation. If you don’t see any signs of mould and the brew is slowly becoming more acidic, give it time. 

Managing High Temperatures 

In warmer weather, your kombucha will ferment faster. However, too much heat (above 37°C) can kill your SCOBY. If the temperatures are too high, consider these options: 

  1. Move to a Cooler Spot: Relocate the brewing vessel to a cool, dark area of your home, such as a basement or a closet. 
  2. Air Conditioning: Keeping your vessel near an air vent can help regulate the temperature. 
  3. Refrigeration: In extreme heat, you can place the brewing vessel in the fridge for a few hours to bring the temperature down temporarily before returning it to room temperature. 

If your kombucha ferments too quickly and becomes overly acidic, you can still use it as extra-strong starter tea for future batches or flavour it to balance the acidity. 

Choosing the Right Brewing Location 

Where you place your brewing vessel matters, especially during the first fermentation, when your kombucha is covered by a breathable cloth. The environment can affect the bacteria and yeast that grow, so choosing the right spot is important. 

Best Location Tips for First Fermentation (F1) 

  1. Good Airflow: Keep your brewing vessel in a place with good airflow, like a kitchen countertop or an open shelf. Avoid placing it in closed cupboards or musty areas, as this can introduce unwanted bacteria or mould. 
  2. Away from Direct Sunlight: While some light exposure is okay, avoid placing your kombucha in direct sunlight, as the sun’s anti-bacterial properties could interfere with the fermentation process. 
  3. Keep Away from Chemicals: Avoid areas where cleaning products, air fresheners or other chemicals are used. The SCOBY can absorb airborne chemicals, which can harm your brew. 
  4. Separate from Other Fermenting Foods: If you’re fermenting other foods like beer, yogurt or kefir, try to keep them at least five feet away from your kombucha to prevent cross-contamination of yeasts and bacteria. 
  5. Avoid Moisture and Mould: Moist or mould-prone areas, such as next to houseplants or near trash cans, should be avoided. 

Location Tips for Second Fermentation (F2) 

Since second fermentation happens in sealed bottles, location concerns are less critical. However, here are some good practices: 

  1. Closed Cabinet or Cooler: Keeping bottles in a closed cabinet or cooler without ice can help contain any potential mess from over-carbonation or bottle breakage. It’s a safety precaution in case the bottles build too much pressure. 
  2. Away from Sunlight: Like with F1, keep your bottles away from direct sunlight. The warmth from the sun can increase pressure inside the bottles and cause over-carbonation. 

Conclusion 

Maintaining the right temperature and environment for your kombucha-brewing process can make a big difference in the quality of your final brew. By keeping your brew within the optimal temperature range and choosing a good location with proper airflow, you can ensure a healthy, successful fermentation every time. Be mindful of seasonal temperature changes and adjust your fermentation times and practices accordingly!