Hi Yelena, there's no need to be concerned about the aroma of your sourdough starter at this point in the process. In the early days of sourdough starter development, your starter is busy weeding out the unhelpful (and sometimes stinky) bacteria, and gradually setting up a healthy balance between wild yeast and lactic acid bacteria (LAB). While you certainly don't want your mature starter to smell like vomit or smelly feet, trust that your starter's aroma will improve dramatically by the time it's rising predictably. 

Barb

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