It really annoys me when someone tells me I can't use easily obtained items to do something that our ancestors have been doing for thousands of years. Do I really need a packet of this and that strange powder? All of these cultures started somewhere.
So I'm sharing with you what I've discovered.
First, there are Mesophilic and Thermophilic Cheese Starters. Let's simplify that a bit - meso means middle, thermo means heat, and philic means loving. So Mesophilic cultures like warmth and Thermophilic cultures like heat.
Let's simplify it a bit more. We'll call Mesophilic Culture "Clabber Starter" and we'll call Thermophilic Culture "Yogurt Starter" or "Whey Starter" .... Oooooh, are you seeing the difference yet? (It's actually a little bit misleading, I think, to call Thermophilic Culture "Whey starter" because you get whey from clabber, too, but let's not be nitpicky.)
Now, be warned that I haven't tried this yet. I'm working on growing my first Clabber Starter (I really want to make some Cheddar!), but I just do not have the milk supply necessary to make a stable Whey Starter. You'll see why - it takes some dedication and plenty of milk.
To Make a Thermophilic (Whey) Starter
A thermophilic starter is one in which all of the mesophilic bacteria, which do not like heat, are killed, and only the heat-tolerant bacteria are left.
Many delicious cheeses use whey starters, including Parmigiana. As with sourdough, the variety of microorganisms in the starter contributes to the regional variations in flavour - so your homemade Parmesan, especially if you maintain a culture from one batch to the next, won't taste exactly like mine.
Heat fresh raw milk to a temperature of 125F and hold it there for 20-30 minutes. This will kill the mesophilic bacteria and common pathogens. The lactobacilli necessary for a thermophilic culture are more resilient and will not die at this temperature.
Cool milk to 110-115F and hold it at this temperature, well-covered, until the milk coagulates. This can takes several days. A traditional method of doing this is to put the hot milk into a clay container and setting it in the hot summer sun.
When the milk thickens, measure it. Remove 90% of it for immediate use – strain for a quick cheese, stir it up and use in cooking, etc. Set aside the 10%.
Begin the process again with fresh raw milk (heating it to 125F). When the milk has been cooled to 110-115F, add the retained milk. This inoculates the next batch. Again, cover and keep it at about 110-115F until it thickens.
Repeat this process between seven and twenty times until the results are consistent from one batch to the next. The curd should be like yogurt and taste pleasantly tart. It is not enough to do a few batches. This must be repeated at least seven times to obtain a stable culture.
When the culture is consistent, make a thermophilic cheese like Parmesan, using the culture as inoculant at a rate of 5% retained whey to the volume of milk used.
When the whey is strained, retain it.
Keep the whey at 105F for 24 hours and then repeat the SAME cheese recipe (for example, Parmesan), use 2-2.5% (of the volume of the milk used) of the retained whey as starter. At this point, the starter should be active, consistent and stable, and it should be between 4.0 and 4.2pH. (A little higher or lower is fine, but not by much).
Retain the whey from the second batch and make the same cheese again the next day, for a third batch of cheese.
Repeat this several times. When a month has passed from the beginning of the process, the bacteria should have developed a stable ecosystem. At this point, the whey can be used to replace any thermophilic starter.To Make a Mesophilic (Clabber) Starter
A mesophilic culture is one in which the less heat-tolerant bacteria are allowed to acidify fresh milk. Clabber, kefir and piima are three common mesophilic cultures. The easiest of these, if you have fresh raw milk, is to use clabber – it works using natural bacteria in the milk.
Many cheeses use a mesophilic culture – Cheddar, Colby, Feta, Chevre, Camembert, Gouda and Blue, for example. These are usually soft cheeses, and some hard cheeses that are not heated over 120F.
Leave raw milk at room temperature, covered lightly, until it thickens. Remove most of it and use to make any sour milk recipe (pancakes, cornbread, biscuits). Replace the amount with fresh milk. Continue the process, as with the thermophilic culture recipe, until the results are consistently thick and pleasantly sour.
Some cheesemakers use a combination of starters – half clabber and half yogurt reportedly makes a very nice Cheddar.
Use about 1/3 cup of this homemade culture per gallon of milk.