Kombucha 茶 pH 值

• 酸度低於 4.6 pH 有防止外來的黴菌或酵母菌(防腐防霉)。
  使用starter tea(老滷汁) 就會起到防腐作用。
  pH值的定義是：pH=-log[H+]
  稀釋10ⁿ倍 pH降低n個單位
  老滷汁用10%就夠了
• 發酵7-14天以後，酸度會達到3.2 pH和2.8 pH之間。

Kombucha tea and pH reading ?

For kombucha tea beverage pH, you should take two readings, one as you add the starter tea to the new
batch of tea. This first pH test reading should be below 4.6 pH, if it is high then keep adding starter tea
from your old batch until the desired pH is reached.

This insures that the fresh tea solution is acidic enough to combat any foreign molds or yeast.

The second time you'll wish to test, is at the finish of the brewing/culturing process.

After your tea has set for the required amount for time, 7 to 14 days in most cases,
then you'll want to test the pH until it is at, or close, to 3 pH.  Range is between 3.2 and 2.8 pH.

This reading tells you that the brewing cycle is complete and the tea is at the correct pH point to drink.
Of course, this can very a bit to suit your needs and taste.

If this final pH is to the alkaline side of the pH scale, then the tea will need a few more days to complete the brewing cycle.

pH Chart for Brewing/Fermenting Kombucha Culture Mushrooms