Soma bottles are polypropylene, unlike many other bike bottles, and seem taste-free.
In contrast my
Hydrapak bladder rendered water undrinkable with a taste that persisted after multiple overnight washings including adding activated charcoal + water, vinegar, and using dilute ethanol + activated charcoal. I discussed this with the company including my concern this was another made in China contamination problem (similar to the toxic toothpaste, toxic pet food, and numerous lead painted toys). "FDA approved food grade polyurethane"? Well maybe, but what else is in it or coating that polyurethane?