Hi PJ, you certainly can, although I'm always a little reluctant to encourage bakers to cultivate multiple starters for themselves, since it makes more sense to build the quantity of your initial starter when you need more. That being said, if you have a friend who wants to try their hand at sourdough baking, you can certainly get them started with some of your discard. If your starter isn't fully mature, I would wait until its rising predictably and has a pleasant aroma before sharing, simply because it can be confusing to get a starter midway through the creation process. A mature, stable starter is a true gift, but a starter that hasn't quite made it there could prove a struggle. 

Barb

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