Homemade yogurt (made in slow cooker) with blueberries, bananas, and walnuts.

I realize that the title of this blog has got some of you scratching your head. Isn’t this blog supposed to be about adoption or infertility—at least in some tangential way? I could lie to you and tell you that there is a connection. Like making your own yogurt saves money so that you’ll better be able to pay for treatment or for adoption, or have more money to spend on those precious kids. Or I could say that homemade yogurt is so deliciously healthy that you’ll live longer and healthier, and thus be better able to parent. But, I’m not. No, the truth is that in addition to being an adoption and infertility research geek, I’m also a food geek. And this discovery was just too good and easy not to share.

I like yogurt, but I like expensive yogurt—the kind without fillers, pectin, gums, or gelatin. I like thick creamy yogurt that has the whole milk taste without the whole milk calories. I read food porn, er um food blogs, frequently and have run across the creamy qualities of homemade yogurt, but all of them used yogurt makers, and I didn’t have a yoghurt maker. I also didn’t want one. I am kitchen gadget averse. I don’t have the space to store them and somehow a gadget-filled kitchen seems amateurish to me. (Given the number of gadgets I own, that makes me both an amateur and a hypocrite.)

My interest in homemade yogurt stayed at the dreaming stage, until I read one particularly enticing recipe. It finally occurred to me that people have been making yogurt for eons and long before yogurt makers existed. Surely it couldn’t be that hard. I went to visit my best friend Ms. Google to study the chemistry of yogurt making. (A classic definition of a food geek is one who starts by researching the chemistry of the food.)

Basically, yogurt is fermented milk. The fermenting agents are specific bacteria that consume lactose – the sugar in the milk – and excrete lactic acid as waste product (it’s best not to focus on the visual image this part conjures up). The lactic acid is what gives yogurt its twang and thickness. These bacteria need warmth to work their magic. In order to thicken and set properly, yogurt needs to be kept at around 110°F for at least 4-6 hours. Yogurt makers are great at maintaining that temperature, but it occurred to me that my good old (and I do mean “old”—notice the avocado green color which classifies it as an antique) crock-pot is also pretty darn good at maintaining temperature, and I’d only have one pot to wash. As with most of my great ideas, I wasn’t the first to think of it, and I owe the basic concept to Stephanie over at A Year of Slow Cooking, and I later found another tutorial at The Girls’ Guide to Guns & Butter.

The process couldn’t be easier, but there are a few “tricks” to getting consistent thick lusciously creamy yogurt.

How to Make Thicker Homemade Yogurt in Your Crock Pot

Homemade yogurt is usually thinner than the store bought variety. This is because much of the yogurt sold at grocery stores have added thickeners such as pectin and gelatin. If, like me, you prefer your yogurt the consistency of Greek yogurt, there are some tricks you can use without resorting to gelatin or other additives.

  • First heating the milk to around 180 degrees. Heating milk alters the milk protein so that they hold more liquids in their web-like matrix after culturing, thus resulting in a thicker creamier yogurt. Apparently the yogurt will turn out fine if you heat a little above 180 degrees as well.
  • Adding powdered milk to your milk mixture. I’ve tried it both with and without powdered milk and think I like it better with the powdered milk added. Plus it increases the protein and calcium.
  • Straining the finished yogurt. The liquid in yogurt, called whey, is by nature “unstable” and easy to separate. That’s why you’ll often see whey in the store bought yogurt that doesn’t use additives. You can thicken the yogurt by draining off some of the whey in a lined colander. I have used cheese cloth and coffee filters to line the colander and both worked fine. I’ve read that you can use paper towels as well, but the best idea I’ve heard is to use flat unfolded birdseye cotton diapers. They are the right size and you can wash and reuse. I’ve already added them to my grocery list. How long you drain depends on how thick you want your yogurt and how scatter-brained you are. The first time, I forgot that I had set the pot of draining yogurt in the outside refrigerator, so it drained for over 24 hours. As luck would have it, the final product is perfect for me. I save the whey and add it to smoothies and soups.

What Type of Milk to Use to Make Yogurt?

I’ve read a lot about what type of milk you should use to make yogurt, and let me tell you, food writers are an opinionated group! Only use whole milk, fat content doesn’t matter, use raw milk, don’t use raw milk, add powdered milk, don’t use powdered milk, and never ever use ultra-pasteurized milk. I’m not an expert, but from what I’ve read and experimented with, I don’t think it matters. Although, you won’t get consistent results using raw milk unless you pasteurize it yourself to kill off the competing bacteria that will often crowd out the yogurt making bacteria.

I was going to start with whole milk yogurt because I had read it was easier to make. I use organic milk and the brand I like best is ultra-pasteurized, so I bought another brand that was pasteurized, but not ultra-pasteurized. I’ve been battling to lose a few pounds as of late and had weighed myself the day I was going to make my first batch. I wasn’t pleased with what I saw on the scales, so at the last minute I decided to switch to making 2% yogurt by mixing equal portions of whole milk and skim milk. . Without even thinking I used 4 cups whole regular pasteurized milk and 4 cups skim ultra-pasteurized milk. The end results were just fine, and I’ve since read a food blog by someone who routinely makes yogurt with ultra-pasteurized milk. Next time I’ll use all ultra-pasteurized milk.

How do you Get the Good Yogurt Making Bacteria in the Milk?

You will have to add the lactose gobbling bacteria to your milk so it can work its lactose eating and discharging magic. For the first time, you’ll need to buy yogurt. Any yogurt will work if it says it contains live bacteria, but I would personally avoid those with fillers just because I don’t want to pollute my final product.

After the first time you can use your own yogurt as a starter. I’ve read varying reports on how effective this will be. Most say that your homemade starter is good for around 4 batches, but others say that as long as it is relatively fresh is does not “wear out”. I am going to try to keep using mine unless I see that the yogurt is not firming up. I have read that you can freeze the store yogurt in starter size portions.

There is also a disagreement about how much starter to use. For 8 cups of milk, I’ve read anywhere from 1 tablespoons to ½ cup. The first thing I read said ½ cup, so that is what I used. Apparently, there is a great deal of flexibility, although one food writer warned against using too much because the bacteria need room to grow.

The Yogurt in a Slow Cooker Technique

8 cups milk

1/2 cup powdered milk (optional)
1 T to ½ cup starter yogurt

Add milk to your crock-pot.

Notice the avocado green.


You want to heat the milk on the low setting until it reaches around 180 degrees F. The exact time could range from 2-4 hours depending on the slow cooker you are using. In theory, you should probably take the temperature of the milk at 2 hours. For my crock-pot, 2 ½ hours worked. Once you have heated the milk to around 180, turn off the slow cooker and let it sit until it reaches around 110 degrees. This will probably take about 3 hours.



In a separate bowl stir about a cup of the milk with your starter until it is well blended. Add back to the crock-pot.


You now need to hold in the warmth for at least 6 hours undisturbed, although I prefer overnight. The method I’ve used is to wrap your crock-pot in a blanket.

Another method is to set the inner crock-pot bowl in an oven with the oven light left on overnight. I haven’t tried that method yet, but will on my next batch.

I do know how geeky this sounds, but honestly, the next morning, I promise you’ll feel like you’re unwrapping a present when you open your crock-pot to see nice semi-thick creamy yogurt.

This batch was made without the added powdered milk and was thinner than usual.

If you want it thicker, strain it.

This is the whey that will drain off the yogurt.

Voila-wonderful smooth creamy delicious yoghurt.

Fresh yogurt is much milder than the store bought variety. If you want it tarter, you can leave it out longer. It will also gain twang in the refrigerator, although at a slower rate.


  • I continue to make it by the time rather than temperature, and it is working just fine.
  • I now use the flat fold birdseye cloth diapers, and they are terrific. I’ll never use cheese cloth again–for anything. The diapers work so well, and then you can just wash and dry them. Make sure you get the flat fold, and not the pre-folded. The only brand I’ve seen is Gerber.
  • I make it now using ultra-pasteurized milk and have had no problems.