I am brewing ginger beer for the first time ever. In fact this is the first time I am brewing ever. I used 200 grams of sugar, 100 grams of yeast, a few mint leaves, and a whole lemon (sliced) in 1.5 liters of water and boiled the mixture. Then cooled it and added 1 teaspoon of baker’s yeast, squeezed one lemon in it and put it in an airtight bottle with an airlock. I cleaned all article with hot water prior to use. 7 days down the line, I opened the bottle and found that the brew to be sour in taste (it does smell of alcohol). Is it possible that there is vinegar in the brew? Is there any test to find out if there is vinegar in the brew pls.?

Looking forward to your advice.

Thanks and Regards,

Arvind Gupta

  • Why would you boil the yeast then add more yeast? That only kills the first yeast.
    – Chloe
    May 18, 2020 at 20:57
  • To remove any other micro organism and when the liquid cools down; introduce fermenting yeast. May 19, 2020 at 19:14
  • I have a better idea, and will save you money! Don't boil your yeast! Only add yest after the water/wort/must has cooled down!
    – Chloe
    Jul 23, 2020 at 3:21

1 Answer 1


Vinegar has a fairly distinctive flavour. If you can't taste it, I would say no.

During fermentation, the yeast rapidly uses-up all the dissolved oxygen in the vessel. Acetobacter needs oxygen to turn ethanol into vinegar. So as long as your air lock was in-place, the fermentation will maintain a positive pressure of carbon dioxide. So there should be no dissolved oxygen, and thus no acetobacter.

Could you be tasting the lemon? Some aspect of the mint?

It could also be another souring bacteria, like lactobacillus. But with good sanitation this should not be an issue.

And while I've never used yeast as it's own nutrient, 100 grams seems like a huge amount.

  • I agree with Kingsley, the amount of yeast in your recipe sounds like a lot. I believe I used only 1 or 2 grams of yeast in my last batch and that was an Ale yeast, but I do have an active and healthy ginger bug that uses natural yeast. Secondly, the type of yeast you are using is for baking, not brewing... not that it can't be used for brewing, but I have yet to hear/read a positive result from people using baking yeast in place of brewing yeast. Baking yeast tends to leave residue and off-flavors. That might be what you are smelling/tasting.
    – jc allen
    May 13, 2020 at 20:10
  • Sorry for the typo- it is 100 grams of ginger and 1 teaspoon of yeast !! Also, there was no minty (or gingerly) flavor. I used baker's yeast as I was trying brewing for the first time. Wine yeast is a little expensive - so no results would have led to wastage. is there any cheap alternative to commercial wine yeast? May 14, 2020 at 19:21

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.