Guessing this is also important in making kefir…
I know for making yogurt, it’s important that the bowl/dish/vessel (glass or ceramic) is sterile before use. Pour boiling water inside and out and let it sit.
Do not touch the inside rim with your hands. Whatever strains of bacteria are in the container will grow. You probably don’t want to be consuming whatever germs are on your hands or sponges.
Yep yepp