I’ve been eating homemade yogurt for awhile now, made from fresh raw whole milk produced by pastured Jersey cows (the gold standard in raw whole milk). I’ve been eating it because I have longstanding digestive issues, and eating yogurt once or twice a day just about eliminates those issues. My husband did a great post on how to make homemade yogurt without a yogurt maker, and I did a blog post on making homemade yogurt with a yogurt maker.
However, as I noted in my blog entry referenced above, and as a little searching online would confirm, homemade yogurt does not have the consistently smooth, thick, creamy texture of store-bought yogurt (which is usually achieved with additives like vegetable gums, which are not always easily available for individual consumers). Homemade yogurt tends to have a softly lumpy texture, with the “lumps” swimming around in the clear whey. Now, it’s still really good for you, and probably far more nutritious than store-bought yogurt – especially if you don’t add any sugar to it. But if you’re accustomed to store-bought, it can be a rough transition to eating homemade, and it’s also not something that looks very appealing to, say, houseguests, or anyone else you might be trying to convert to the homemade yogurt cause.
So, it’s not surprising that there are a number of ways to thicken homemade yogurt, in an attempt to give it a better appearance and mouthfeel. I did some online research awhile ago, and I found four different yogurt thickening techniques: straining to remove whey; adding powdered milk; heating milk to 180 degrees F; and adding gelatin. I tried a couple of them, and didn’t try the two others for good reasons. Below I discuss my experiences using straining and gelatin, and also why I did not try powdered milk or heating milk to 180 degrees.
This yogurt thickening technique is simple and makes sense – strain the finished yogurt through cheesecloth to remove whey (although some people mentioned using coffee filters, or a clean t-shirt). I used a few layers of cheesecloth, draped over a sieve and set over a bowl to catch the whey. I let it drain for about an hour.
However, as it turned out, I wasn’t able to just put the yogurt in the cheesecloth and walk away. A film formed after awhile on the cheesecloth, impeding drainage, so I kept scraping the yogurt around, to open up some areas in the film to let the whey continue draining. As you might expect, it’s a lot of bother to keep doing that.
Result: the yogurt was definitely thicker, somewhat closer to smooth and creamy but still lumpy looking. It had a much smaller volume than the original yogurt; I’d say I ended up with one-third yogurt and two-thirds whey.
Con: a lot of work, what with all the scraping, and resulting yogurt is considerably reduced in volume. To be fair, some websites I read said to just leave the yogurt for several hours or overnight, but I wasn’t that patient; maybe it would have drained well on its own, with more time.
Recommendation: I’d recommend using this method mainly for obtaining whey, and also if you’d like to use the resulting yogurt as a very tasty substitute for crème fraiche or sour cream (although again, it would not be as smooth and creamy as store-bought crème fraiche or sour cream, since like store-bought yogurt, they are usually made thick and creamy by additives). I’d also recommend this method if you don’t want to use any of the other three methods discussed below, as it is the most natural of all four methods mentioned in this post.
A lot of people use powdered milk to thicken their yogurt, although I could not find a consistent suggested amount; recipes varied considerably. I decided to not even try this method (after, of course, already buying a package of powdered milk) for a number of reasons:
Extra carbs: the only powdered milk available around here is the non-fat kind, which means I’d be adding extra carbs and protein to the yogurt. The protein would be okay, but not the carbs, since I eat low-carb and milk is already a somewhat carby food (although yogurt is a bit less so, since some of the sugar is used by the fermenting bacteria).
Taste and texture: some people commented that they didn’t like the taste of powdered milk, and I felt reasonably certain I wouldn’t either. I don’t like skim milk – why would I like it powdered? Others commented that sometimes powdered milk added a gritty texture – not what I’m going for.
Nutritional quality: I honestly can’t imagine powdered milk being highly nutritious, especially since this milk is probably from the usual sort of conventional dairy cow – confined in a stall 24/7, being fed distillery swill, antibiotics, and growth hormones, never getting to soak in some sunlight or fresh air, or even just take a walk once in awhile. Such cows produce poor quality milk (which is why it needs to be pasteurized and supplemented with vitamins), and the quality is reduced further by the pasteurization and dehydration process. Yuck.
Heating Milk to 180 degrees F
This method thickens yogurt a couple of ways, dehydration (which depends on how long you heat the milk) and protein denaturing, which occurs at high temperatures (here’s a simple explanation, a technical one, and a really technical one). I didn’t try this method either. I don’t want to denature highly nutritious raw whole milk; I want the nutrient content to be as whole and intact as possible (although some people using high heat with raw milk do have their reasons). Also, this method pasteurizes the milk, killing off a lot of beneficial bacteria that are naturally present in high-quality raw milk. These beneficial bacteria are good for the digestive system, and they also fight off pathogenic (disease-causing) bacteria, both in the milk, and in your gut.
Recommendation: If the only milk you can get is store-bought pasteurized milk, you’ll have to use this method in order to produce safe yogurt. Pasteurized milk has had all the beneficial bacteria killed out of it, leaving it extremely vulnerable to “infection” by pathogenic bacteria between the time it’s pasteurized and the time it gets put in your fridge. By pasteurizing the milk again, prior to adding the yogurt culture, you are giving the beneficial yogurt culture bacteria enough of a head start that they can outcompete or kill off any new pathogenic bacteria that will inevitably get introduced into the milk in your home environment (no offense! Bacteria are everywhere).
This is my preferred method for thickening yogurt. I simply add a packet of Knox gelatine powder (2 teaspoons) to two quarts (8 cups) of milk, as I’m heating the milk up to 110 degrees F. (No need to “pre-soak” the gelatin in a separate container. I just sprinkle the powder on top of the milk, distributing it as evenly as possible, wait a few minutes, and then whisk it in with a fork) This method produces some very good, reasonably thick yogurt, although it doesn’t thicken up until after the finished yogurt cools in the fridge and the gelatin sets up. Note: You can also use more or less gelatin for different texture. I just made a two-quart batch using only 1 teaspoon of gelatin (half a packet) and it turned out real well – still with a thick and creamy texture, but not as firm as when I had used 2 teaspoons.
Pro: considerable improvement in texture and thickness, with good appearance and mouthfeel. I wouldn’t be ashamed to serve this to other people, although still with the caveat that it is homemade, because it’s not perfectly smooth and creamy like store-bought yogurt.
Con: If you’re using small packets of dried gelatin powder, and you want to make significantly more or less than two quarts of yogurt, then you’ll have leftover gelatin you’ll have to store somehow (it needs to be kept dry). You also won’t be able to strain whey out of this yogurt, since it is bound up with the gelatin. Finally, if you are avoiding animal flesh products, then obviously you couldn’t use gelatin; there are, however, substitutes for gelatin, including vegetable-based ones, although you might have to experiment to figure out which one you like and how much to use.
Recommendation: this is the easiest method for thickening homemade yogurt. You could also use this with any of the other methods. I’d recommend varying the amount of gelatin you use to see what texture you prefer.
Final note: it is important, while the yogurt is fermenting, to not jostle the container(s); this will interfere with the formation of the yogurt texture, regardless if you are using any thickening technique or not. Be sure to ferment your yogurt in an out-of-the-way place where it will not be disturbed.
I’m glad I finally got around to researching this topic and learning how to thicken yogurt up to a texture that I like. Before I started thickening it, eating it could almost seem like a chore, since the texture and appearance were not appealing, and so sometimes I avoided it, to my own detriment. I enjoy eating my yogurt now, though, and I certainly enjoy having a happy, well-functioning gut!