Greek yoghurt

I’ve been down a rabbithole. I started with some research about the probiotic bacteria in Dosa batter, and how good it is for you. I like Dosa and we eat it a bit, so the research was fascinating. But it led me on to research about lactic acid bacteria and the surge in recent research about the relationship between gut microbiomes and all sorts of physical and mental health effects. Which then led me into fermented foods and all the different genera of lactic acid bacteria used in food fermentations… and now, a few days later, I’m thinking I should just publish the post that has been sitting in drafts for ages about Greek yoghurt.

It’s been in drafts for ages because there are plenty of recipes for yoghurt online. But mine is quick, easy, simple and cheap enough that, like sourdough, it’s become one of those routines that I’ve found worth doing even when life gets crazy busy. The big message in all the research was that lactic acid bacteria are so hugely healthy they really should be in our diet every day, and yoghurt is one of the easiest, cheapest, most reliable ways to do that.

I make a kilo of yoghurt at least once, often two or three times a week depending on what I am cooking. It goes with fruit salad for breakfast (often), in baking, in curries, in Middle-eastern style garlic yoghurt sauce, in tzatziki, in labne, with vanilla or jam or stewed fruit swirls for kids’ school lunches – it’s one of those fridge staples that makes for a lot of possibilities. Made with powdered milk, it works out at around $1.70 a kilo.

So, this is my everyday method, and I’ll add some options at the end.

I picked up an EzyYo thermos an container at an opshop years ago. The container holds a litre, which makes a kilo of yoghurt. (Alternatives to the EzyYo equipment in the options at the end).

The yoghurt container is never washed up, and I never use the last of the yoghurt. When I get down near the end of the yoghurt in the fridge, I just leave about a dessertspoon full in the container. I made the mistake when I started of thinking more starter would make it more reliable, but this isn’t so. You only need a couple of teaspoons of starter, and more than a couple of dessertspoons full will make the yoghurt grainy.

To that dessertspoon, I add enough full cream milk powder to make a litre, plus two big dessertspoons extra. The instructions say 140gm milk powder is the right amount for a litre, and the easy way is to tare the yoghurt container on the digital scales, add 140gm, then another two spoonfuls making around 170gm.

I put warm tap water in a jug and half fill the containter with it. “Warm” means fairly specifically 36°C to 45°C. Too hot and you’ll kill the starter culture, too cold and non-yoghurt-making bacteria will invade. I use a thermometer and aim for water at the warm end because the starter, out of the fridge, starts out cold.

I use a stick blender to blend it all together, scraping down the sides of the yoghurt container with a spatula to make sure all the starter is blended in. Then I top up the container with the warm water and put it in the thermos.

The thermos is filled with boiling water to just above the central red baffle. When the yoghurt container is in it, the boiling water reaches three quarters of the way up it. Lid on, and I cover the top with a fluffy teatowel just to provide a little more insulation.

If I make it in the morning, the yoghurt is ready by the evening, but I like it a little sourer and more cultured so I usually leave it till the next morning – a full 24 hours – before putting it in the fridge.

That’s it. The whole process takes five minutes tops. (The flour you see in the image is me making sourdough pita at the same time.)

The Options:

You don’t need an EzyYo thermos and container (though they seem to come up in op shops all the time). All you need is some way of keeping your yoghurt warm and undisturbed – not too hot, not too cold – for a whole day. I have made it in the past just by wrapping it up in a dark coloured wool blanket and putting it out in the sun, or sitting it on top of the hot water system.

You don’t need to already have a culture going. You can start with any “pot set” full cream yoghurt from the supermarket. (I think I started with a Jalna culture).

You don’t need to make a kilo at a time. Just mix up the amount of milk you want, but you need to add a little extra milk powder to make it thick and Greek.

You don’t need thermometer. You will pretty quickly get a feel for how warm it needs to be just using a finger. It should feel warm, warmer than you would make a baby’s bath but not so hot that you’d have to sip it if it was a drink.

You don’t need a stick blender. Any way of thoroughly mixing the starter culture into the warm milk will work – an ordinary blender, a whisk or even just a jar and shaking. You do want it thoroughly blended in though.

You can use fresh milk or UHT milk (though that makes it not quite so economical). UHT is easy – just warm it to around 42°C. Fresh milk is harder. You need to first bring it up to just below boiling, to the point where it is just about to start rising in the saucepan, then cool it to around 42°C. This changes the structure of the proteins in it to make it easier for the yoghurt culture to get a hold. But add a couple of spoonfuls of milk powder if you want thick Greek yoghurt. (The other way to get it thick is to strain the finished yoghurt through some cheesecloth, but adding milk powder is much easier).

Yoghurt is just one of many, many fermented foods that contain lactic acid bacteria, so if you don’t eat dairy products there are lots of other options. But if you do eat dairy, routinely making your own yoghurt is one of those habits that make you healthy, and the evidence is mounting, in mind and body.