You can make limited variety of cheeses with the mesophilic and thermophilic culture recipes I have given. Sooner or later you will want to be buying commercial cultures from suppliers for specific cheeses and also other cultures for ripening and washing.
The starter cultures are coming in sachets, kept in freezer and they are designed for like 500 or 1000 litres of milk. It would be impossible to measure them according to your recipe as we are using maximum 40 litres of milk in a batch. Also it would not be cost affective if you finish your culture in couple of makings. What are we going to do?
As soon as I receive the sachet, I sterilize a small scissor and the corner of sachet, cut carefully and transfer the culture to a clean and sterile specimen bottle like the one below.
This operation is only keeping them tight and secure. When it comes to using them, I prepare a mother culture according to the recipe given by Cheese Forum member Sailor. this method gives you an active starter culture, measuring will be easier and cost affective too. And let me tell you the real secret. Since I have started using the cultures like in the above mentioned method, the quality and consistency of my makings increased. As the culture is measured correctly and in working order, the acidity curves are getting better and consistent with the time.
The other thing is no matter how old your culture is sitting in the freezer or expired for that matter, you can revive and use it with this method. By keeping the temperatures constant and waiting to a coagulation will make sure that the population of your culture is constant. You don’t need a pH meter, just wait till it curdles like yogurt.
For freezing and labelling your mother cultures, use clean and sterile ice trays and plastic zip lock bags with labels on them.