I read the helpful posts about yeast starter, but still have questions. After adding the yeast starter to my 5 gallons of wort, do I still pitch a full packet of Wyeast in addition? When making my yeast starter does the DME supply the sugar and nutrients or am I supposed add something additional? Say I’m making 2 liters of starter. Do I use a whole smack pack of yeast? When stirring the starter is the flask capped? I want oxygen in , but aren’t I concerned about wild yeasts and other contaminents if everything is open.? Didn’t I go to all that effort to sanitize everything , to now just leave my starter uncovered for 12 - 18 hours? What should I do ? Start to Finish? Thanks
Use the full packet of yeast to make the starter. Assuming the yeast starter was of adequate size (see http://www.mrmalty.com), that’s all you need you shouldn’t need to add another packet.
I add a little yeast nutrient to the starter, but it isn’t strictly necessary. Wort has everything yeast need.
You don’t want to leave your starter wide open (although honestly you could probably get away with it). Many people loosely cover it with foil. Or use one of those foam stopper things. You want air to be able to get in, but you want to keep dust particles (and whatever nasties may be clinging to them) out. Shake frequently throughout the fermentation process to encourage more air to get in and improve yeast reproduction. Stir plates are ideal, but I just swirl it on occasion.
2 liters is a pretty big starter, with one that size you want to decant (gently pour) the starter beer off the top once the yeast has settled out. You can chill the starter to encourage it to settle out faster. Just don’t do this until the starter is done, as you will put a stop to all fermentation activity by chilling.
If you didn’t see my post on your other thread, go read howtobrew.com. Its worth your while.
edit: to clarify the decanting thing, the decanted starter beer goes down the drain. Only the yeast at the bottom goes in your actual beer. Leave enough of the starter beer in the flask to swirl around and pick up all the yeast though.
