How to catch culture out of yogurt?

Question

When I make yogurt, I freeze some of the yogurt for the next time. However, I concentrate the yogurt by pouring it into a cloth, and extracting the yogurt whey (I do not know if it is called whey like cheese).

1. Is the culture in the yogurt whey? Do I lose culture by concentrating the yogurt?

2. Is salt harmful for the culture? Do I necessarily need to store the culture before adding salt to yogurt?

Answer 1

The culture is everywhere in the yogurt, and you are not losing all of the whey anyway. If you'd managed to press out all of the moisture, you'd end up with yogurt powder.

Salt interferes with all kinds of microorganisms. It is much better to not add salt to culture.