Yes, it's perfectly normal to see sediments or jelly-like blobs in bottled kombucha. These are signs of a healthy, living culture and are harmless.
The sediments and jelly-like blobs you see in kombucha are primarily cellulose, a natural byproduct of the fermentation process created by the SCOBY (Symbiotic Culture Of Bacteria and Yeast). The SCOBY consumes the sugar and tea in the kombucha, producing various acids, gases, and cellulose. This cellulose can clump together and form visible particles or even a new, thin SCOBY layer within the bottle. These formations are often referred to as 'floaters' or 'baby SCOBYs.' Their presence indicates that the kombucha is raw and unpasteurized, meaning the beneficial bacteria and yeast are still active. Some kombucha brands filter these out for aesthetic reasons, but their presence is a sign of a naturally fermented product. The amount of sediment can vary from bottle to bottle, depending on factors like the specific culture used, the fermentation time, and storage conditions.
If you find the sediment unappealing, gently swirl the bottle before opening to redistribute it, or pour the kombucha through a fine-mesh strainer to remove the particles. This won't affect the taste or benefits of the kombucha.