Ludicrously Thick Greek-Style Home-Made Yoghurt (Using Only Powdered Milk)
I’m a big fan of yoghurt that’s thick and healthy. I don’t like sweet yoghurts (I mean I do, but they’re not an “everyday food”). I just want a yoghurt that’s thick, rich, high in protein, healthy, inexpensive, and easy to make.
That’s why I came up with this method for making yoghurt at home using very affordable ingredients. I use milk powder, which is both cheap and pre-sterilised. No need for milk, even. So I don’t need to boil the milk — I just throw in a culture and incubate it!
Most people have blenders (or at least a hand blender, which is fine). But the part of this recipe that’s complex is the sous vide bath. It’s just the best way I have for keeping something at the right temp. You can also put it in an oven, or wrap it in a blanket, or do whatever you want to keep yoghurt at the right temp. I don’t live in a place that’s consistently warm enough for those methods to be practical, which is why I use a sous vide bath.
Home-Made Yoghurt Nutritional Information
The following is based on using the ratios below, with a 50/50 blend of skim milk powder and full-fat milk powder.
| Item | Per 100g | Per 200g serving |
|---|---|---|
| Protein | 8.2 g | 16.4 g |
| Fat | 4.2 g | 8.5 g |
| Carbohydrates | 12.4 g | 24.8 g |
| Energy (approx) | 504 kj (120 kcal) | 1008 kj (240 kcal) |
The fat content comes down if you use all non-fat milk powder. But considering how thick and creamy this yoghurt is already, I think this is pretty good! Most of the energy in this comes from carbohydrates, anyway, which come from the lactose in the milk powder.
Cost of Home-Made Greek Yoghurt
Based on my analysis, this yoghurt costs $2.80 per kg. This compares with the price of a basic tub of Greek yoghurt at $4.50 at most supermarkets.
That’s using Australian prices. But I poked around on some US online supermarket prices (Safeway for a lower-end price) and see that generally, this comes out cheaper than most basic yoghurts, and a lot cheaper than the high-end yoghurts.
So yes, you’re not saving a ton of money, especially considering how much you eat in a day. But there are still two reasons why you’d make yoghurt at home: 1. Quality, and 2. lower waste (no containers to throw out).
Yes, you can also bulk-buy Greek yoghurt fairly cheaply. But those would be high fat.
“What about energy cost?” you ask. Good point. If you’ve skipped ahead, you’ll see that you’re running a sous vide circulator all day. If you use cold tap water to start, then there’s a 15-minute ramp-up time, plus eight hours of running time.
At today’s high energy prices this means
- 1000W * 0.25 = 0.25 kWh
- 100W * 8 = 0.8 kWh
Or a total of around 1 kWh. That’s 35c on top of the cost of ingredients, for a total of under $3.20 per kg.
You can also reduce this electricity load by
- Finding some other way to keep the temperature stable
- Running your sous vide in an insulated tub
- Running it in off-peak time (e.g. overnight, if your plan works that way)
- Using solar power
But generally, the cost of power is something to factor if you don’t have those means at your disposal.
What you need (Hardware and Ingredients)
This is what you need to make thick home-style greek yoghurt.
- Hardware
- A sous vide circulator + a container to do the sous vide bath in. (See discussion on this below)
- A sealable container (1.5-2L)
- A blender or blender wand
- Ingredients
- Milk powder (skim or full fat — I use a 50/50 blend)
- Water
- Natural yoghurt
What’s a “sous vide” circulator and why use one? A “sous vide” circulator is an immersion heater that helps you cook using the sous vide method (sous vide really means “under vacuum”).
The sous vide method is primarily for sterilising foods (like meat) so they can be prepared in other ways, but a sous vide immersion wand is an excellent, affordable, and energy-friendly way of keeping something temperature stable.
If you google “sous vide” you’ll mostly find expensive circulators by renowned brands. I first used one of these, then had to get rid of it when I left the US because it wouldn’t work anywhere else in the world (America has low-voltage outlets). After that, I bought a cheap one on eBay and it performs exactly as well — though the interface isn’t as perfect (it beeps 20 times when it reaches temperature; is that really necessary?)
So, basically, hop on eBay and find any sous vide wand there and you’ll be fine.
Ingredients
Here is how much of each ingredient I use. This is a ratio recipe (much like any recipe for bread or other things you make in bulk) – so you can scale up or down the amounts (or use your own units).
- Water — 1 L (100%)
- Milk powder — 375 g (37.5%). I use 50/50 skim and full fat for a semi-fat yoghurt. (See note below)
- Starter yoghurt — 100 g (10%). It just has to be a natural yoghurt with no added flavours or thickeners.
Yes, those are metric units, but use the percentages to scale up and down. (Americans here may find it difficult to believe that I look at quarts, ounces, and cups and find them as perplexing as you do litres and grams. Did you know that an imperial “cup” is different from a metric one??)
Note on fat mix: I’ve tried this using pure skim milk powder. It’s possible of course. But the yoghurt, while thick, always was a little watery. Fat adds a creaminess that you can’t otherwise easily get.
Method
First, blend your ingredients together. A blender (a simple one is fine) is important to make sure there’s no clumping. Pour the water first, then the milk powder, and blend. Finally, add the yoghurt, and blend that in too.
Together, it should fill up a normal-sized blender.
Next, incubate your yoghurt at 42 degrees. I use a sous vide bath for this, and that’s why I use a sealable container. Incubate it at 42 degrees centigrade (108F) for 8 hours.
Finally, take the container out of the bath, dry it off, and refrigerate. You can’t eat it right away as it’s warm! (Warm yoghurt… weird.)
Other thoughts / questions
How much does it change if you use all skim milk powder? I tested this out, out of curiosity. It’s still very thick and delicious. Many online assume you need high fat content for creaminess. It’s true, fat is creamy, but it’s not mandatory for Greek-style yoghurt.
Why eight hours? Why forty-two degrees? Less than eight hours and the yoghurt will have developed but will not be as tangy. Yoghurt must be tangy.
Forty-two degrees — it’s just a number I picked between forty and forty-five. It works. With a sous vide bath, you can be specific. Yoghurt is actually forgiving within a range, so if your circulator has problems maintaining any temp, it won’t matter.
How much can you keep reusing the same yoghurt? You can keep using the same “batch” of yoghurt culture about 5-10 times before it starts becoming runny and less yoghurt-like. The reason for this is that some cultures start dominating the yoghurt at the expense of others. Commercially, you can’t call it “yoghurt” after a while, as it doesn’t have the right culture mix.
Can you use fresh milk or UHT (long-life) milk? Yes, you can. But you have to boil fresh milk. To both of them, you have to add milk powder. Because I’m adding milk powder anyway, I’d suggest you just do that from the outset to reduce complexity.
