I love yogurt and I use a lot of it in cooking and baking, as well as eating it as is.
After straining, this will be more like Greek yogurt, less dense than cream cheese.
I buy the yogurt cultures from New England Cheesemaking Supply Company
They also have cultures for Sour Cream, Creme Fraiche, Buttermilk, Kefir, Fromage Blanc and Fromagina.
And also from Tribest Yolife
as I have found that my results with the cultures from these vendors are more consistent and the yogurt always turn out exactly the way I like it.
In AUSTRALIA, there is CHEESELINKS a highly recommended vendor (from friends who live in Oz) that carries the various yogurt cultures including one for soy milk (also works with almond or coconut milk, according to a vegetarian friend), and several people report that the Type C6 culture works beautifully with whole milk to which some cream has been added to produce a thick, rich and silky product similar to Greek yogurt.
It is important to prepare the milk, whatever kind your are using, prior to adding the culture. I know that some people do it differently but this way is safe and effective.
I prepare it in 1/2 gallon batches – 2 quarts works well for me because when finished I always take out ONE QUART to place in a strainer to make yogurt cheese. And I SAVE 1/4 CUP to make the next batch – for most cultures you can do this 3 or 4 times.
I don’t add dry milk powder and you can see the texture in the photo I posted above. My results are always consistent using the purchased culture for the first batch and a small part of each batch for three subsequent batches. Then starting over with a new culture.
I tried it a few times with milk powder and did not like either the flavor or the texture. I drained it for yogurt cheese and got much less solids (twice the amount of whey as with my usual batch) which also did not have the texture that I insist on. It was sort of grainy.
Following is a quote from the California Milk Board:
“Yogurt is formed by the growth of two bacterial organisms in milk; Streptococcus thermophilus and Lactobacillus bulgaricus which turn the milk sugars into lactic acid. These are two separate bacteria that are active at different times during processing. Some times you will also find yogurt that contains other “”Probiotic”” cultures such as Lactobacillus acidophilus, Bifidobacterium longum, and Bifidobacterium infantis which are bacterium normally found in your intestines. Together these bacteria aid in digestion and the synthesis of vitamins. Here are the required steps. Heat milk to between 180 and 200 °F. Heating the milk is done for a few reasons. First, to sterilize/pasteurize the milk so that the yogurt bacteria/culture has a hospitable place to grow in. It is not desirable to incubate contaminating bacteria that might be present in the unsterilized milk. Heating should be done even with pasteurized milk to help make a smooth thick yogurt. Heating the milk also helps stop the whey from separating out quite as much. You must then cool milk to 115 °F and add yogurt culture. (If the milk is too hot it will kill the yogurt bacteria.) Stir in yogurt culture gently until dissolved. Hold temperature at 105 to 110 °F for approximately 8-10 hours. This allows your “”good”” bacteria to grow. Finally, you must refrigerate the processed yogurt for at least two hours. Refrigeration help slow the continued bacterial growth. If yogurt is not refrigerated it will become sour.”
I use yogurt for many purposes, which is why I prepare so much.
I use it in place of buttermilk in baking – I think the texture in quick breads is better with yogurt.
I mix it with regular milk (either whole or 2%) in a blender with fruit to make a kefir-like drink. (You can make kefir but it requires a different kind of culture which is somewhat tricky to handle and does not always produce the desired result.)
I use it as a substitute for sour cream.
A cup of yogurt, combined with two tablespoons of frozen orange juice concentrate (I buy organic) is great with cereal. I mix it with Grape-Nuts in the evening and consume it the next morning. That way I get sufficient fiber with my yogurt to make a healthy breakfast. (The Grape-Nuts soften a bit but still retain some crunch.)
Yogurt is healthy. Instead of paying a premium price for the yogurt products that promote “regularity,” when you make your own from a known culture that includes the beneficial organisms, you don’t have any of the additives commonly added to commercial yogurts to extend shelf life.
If you want a fruity yogurt you can add your own fruits. Organically grown frozen fruits are readily available and are much better for you than the sweetened and processed purees that are used in commercial yogurts. You can also add the sweetener you want, including those that are better for diabetics. (I have diabetes so I know the subject well.)
YOGURT, STEP-BY-STEP Production
So this is the process, after you have ordered your yogurt cultures, sterilized your equipment and purchased your milk.
Assemble your equipment and ingredients:
Pour the milk into a microwaveable glass bowl that is large enough to contain 1/2 gallon and will be easy to handle when the milk is hot.
This 2 1/2 quart Anchor Hocking measure is ideal.
If the milk is straight out of the refrigerator, Microwave on high for fifteen minutes in a full power microwave. (Check temp at 12 minutes). Longer if you have one with less power. If I remember to do so, I set the milk out on the counter several hours before I want to start, so it will come to room temp. It is perfectly safe to do this. You will only need to microwave it for about 6 to 8 minutes to bring it to temp.
Check the temp with an instant-read thermometer. ( I recommend the less expensive RT301, or the waterproof RT600C)
Super-Fast Pocket Thermometer made by ThermoWorks.)
The temp should be at least 180° F. If less than that, microwave additional minutes, one-minute increments, stirring the milk each time because temps in the liquid can vary. Up to 190° is fine, it just should not boil.
This is after cold milk has been heated in the microwave on high for 14 minutes.
It will probably take about 90 minutes for the milk temperature to drop from 180°F., to 115° F. at room temp, unless it is quite warm – my kitchen is right at 65° F today. This can be hastened with cooling in a cold water bath if you are in a hurry.
From that point keep an eye on it. Or, if you decide to do this on a regular basis, get one of these very handy probe thermometers that will sound the alarm when the temp drops to the temp you set. Also from ThermoWorks, the EcoTemp Alarm Thermometer which is my favorite because I don’t have to keep watching the milk.
This is the ideal temperature for adding the culture.
First, remove the “skin” that has formed on the surface. It not, you will have thin, leathery membranes in the finished yogurt. Once formed, this skin does not readily dissolve and won’t blend into the milk.
and let it hydrate for a couple of minutes then whisk it into the milk.
If using a non-electric incubator transfer the milk to the inner container, cover and set aside for twelve hours.
plug it in and leave it alone for a minimum of 8 hours. In my opinion longer is better and I almost always let it incubate for 12 hours.
After 8+ hours:
Check the yogurt to make sure it has reached the consistency you want. You can always return it to the incubator and let it “work” for a few more hours as long as it maintains the optimal incubation temperature. (85° to 100° F.)
This batch was not quite as “tangy” as I like so it was back into the incubator. 14 1/2 hours incubation.
I recently made a more solid – Greek type yogurt without straining, using HEAVY CREAM, instead of milk, with a regular yogurt starter culture (from New England Cheesemaking Suply) and allowed it to incubate for 24 hours.
As you can see in the photo it is very firm and holds its shape nicely as a substitute for sour cream.
For the longer incubation I use the YoLife electric yogurt maker to keep the desirable temp for this extended period.
If you don’t have a thermometer that converts to Celsius, this is a good reference: