If batch of home brewed beer fermenting can you just add more yeast?

It's generally not recommended to add more yeast to a batch of beer that's already fermenting. Here's why:

* Yeast Health: Once yeast starts fermenting, it goes through a lifecycle. Adding more yeast can disrupt the existing yeast's progress and lead to off-flavors.

* Flocculation: Yeast flocculates (clumps together) as it finishes fermentation. Adding more yeast can disrupt this process and potentially lead to haze in your beer.

* Competition: Adding new yeast can create competition for nutrients and oxygen, which can lead to uneven fermentation and undesirable flavors.

* Risk of Infection: Adding more yeast introduces the risk of contaminating your beer with unwanted organisms.

What to do instead:

If you're concerned about your beer's fermentation progress, here are some options:

* Check Gravity: Measure the specific gravity of your beer to see if fermentation has stalled. If it hasn't dropped significantly, it might be a sign of a problem.

* Temperature Control: Ensure your fermentation temperature is within the optimal range for your yeast strain. Temperature plays a crucial role in yeast activity.

* Rehydrate and Pitch Fresh Yeast: If you suspect the original yeast isn't doing its job, consider rehydrating and pitching fresh yeast of the same strain. This is a better option than adding more to the existing batch.

* Consult a Brewer: If you're unsure about what to do, it's best to consult with an experienced brewer or homebrew shop for advice.

Remember, brewing is a science and a bit of an art. Taking the time to understand yeast behavior and proper fermentation techniques can help you avoid common issues and ensure a delicious and enjoyable beer.