I noticed that in the video that came with my beer kit, they didn’t rehydrate the dry beer yeast they just added it directly to the wort. Is it okay to do that?
Yeah - it’s okay, although you’ll probably lose a lttle viability of the cells pitched. Depending on the size of your batch, you may want to pitch 2 packets but if it’s a 5 gallon batch I wouldn’t worry about it one bit. Dry yeast are coated with nutrients, so don’t make a starter or you’ll burn up the nutrients and the yeast will stall out earlier than desired during fermentation (speaking from experience).
Yes that’s fine.
You will get some responses here that say hydrate, you will get some that say don’t hydrate, the best thing to do is try both yourself, keep notes and figure out what you prefer.
This a hot button issue in homebrewing. As said above many sprinkle directly onto the wort, while others rehydrate. I’ve noticed faster take off with rehydrating, but as far as the end product, I haven’t perceived a difference.
Pitching dry leads to a 50% reduction in yeast cells, so if you want to just sprinkle the yeast on the wort, make sure you’re using enough yeast to account for the loss. Jamil’s yeast calculator will tell you how much to pitch:
pitching right on the wort will probably kill about half as shadtree mentioned.
I would just rehydrate it is easy and quick and you will not have a bunch of deadcells in your beer