Strange yeast/mold appeared on my starter
I usually feed my starter everyday. I keep it in the kitchen at room temperature. I feed it with rye.
About two weeks ago I left it unfed for a couple of days (the cleaning lady had put it in a drawer) and a strange layer appeared on the surface, very different from other occasion when it was left unfed for too long (where its just turned very sour and watery), and this layer has been coming back ever since, even after 24h, at normal feeding time. It looks a bit scary, but there's no particular smell, and underneath the starter is just as active as ever. I've mad bread with it since, and all is well on that front. The only thing I can think of is that it has been contaminated with something. My housemate has been brewing water kefir right next to it. Could this be causing this. I've decide to store it in a different spot for the time being.
Any advice is appreciated.
I ferment milk kefir and that culture looks very much like one that grows on top of my milk kefir when I let it go a few days or on my kefir cheese. I just did a quick google search and it is called Geotrichum candidum . Take a look at some google images and if you let it grow, it will look like those pics. It is harmless and usually a desirable thing to have....on cheese.
My suggestion is to gently push the top half of the starter to the side, then use a clean spoon to take a sample from the bottom and grow another starter in a clean,sterilized jar. That particular fermenter can be persistent. It might be interesting to let it grow a bit and see how it affects the flavor of the starter-good or bad. Another suggestion is to just put more space between the water kefir and the starter. That may or may not help with future cross contamination.
When you work with cultures, the whole kitchen becomes inoculated. My last kitchen was so imbued with fermenters that nothing in my refrigerator ever seemed to spoil-it fermented. It was an interesting experience and I am working on my current kitchen to raise it to that level.
Just looks like mold, probably came from the drawer it was stored in. Try taking some from the bottom, like a tablespoon (remove about an inch of the top first), put in a clean jar and feed your normal ratios. If no more mold, you should be good. If mold comes back, just get another starter going.