when passing along a whey culture, this needs to be used the next day, or if prepared differently it can be a 2-day culture instead. however, 2-day cultures are less safe and less controllable and today in Switzerland, farmers are discouraged from using them.
You can, however, take a bit of whey and freeze it, then use this to make a new mother culture. Use the whey as a culture to make yogurt, somewhere you can find I have a post here about whey cultures and how we do them.
You would need about 1 liter of whey culture (Sirtenkultur, in Switzerland) for every 100 to 150 liters of milk (precision with the culture is not that important, unlike rennet) or if you make yogurt, about 2 to 3 dl yogurt per 100 liter milk.
hope this answers the question about whey culture.
Also, I posted on your blog but I will say here too, I'd be glad to fill you in a little on the history and why it is Alpine cheeses are made the way they are. In some areas you are right, some you are part right, some, well, not so much. I like to see that our culture is understood, cheese is a very important part of our heritage, and the specifics as to why it is made the way it is and how are also important to who the people are.
I'd also be glad to fill in and show you how your methods compare to the traditional methods, you might be interested in comparing them (like many things, the New World method of making Gruyere is quite a bit different)