Question about yeast and 1 gallon batch

[cantputt87]

I am brewing a test gallon batch of an american wheat. Is 1 wyeast smack pack too much yeast? Is there such thing as too much yeast?

Thanks for the help

 

[Pie_Man]

If I'm trying to test a recipe, I would do my best to keep the inputs at the same ratios that I would use in the full sized batch. So in your case, I would pitch the yeast at approximately the same rate as you would in the full sized batch. If you over pitch the one gallon test batch (I would suspect you are if you pitch the entire smack pack), you're probably not going to ruin the one gallon of beer, but it's going to alter the flavor compared to the full sized version of the recipe and you're not going to have a test batch that's necessarily accurate. Different yeast strains will accentuate the difference in pitching rate more so than others.

I'd use yeastcalc.com to determine the approximate number of cells you're pitching.