My Yoghurt Balance Sheet

An interesting post from Brent Lineberry explained why he no longer makes his own yoghurt and prompted me to examine my own practice.

I’ve made my own yoghurt since forever, when my Mom bought a strange kit that consisted of a tray cover, like the kind you see removed with a flourish in fancy restaurants, only double-walled aluminium, which covered a set of six hexagonal jars that came together with a hole in the middle for a much smaller jar. You heated the milk, let it cool, inoculated with yoghurt from the previous batch, in the smaller jar, poured it into the big jars and the small jar and put the cover on. Twelve hours later, yoghurt.

That’s still my method, in essence. I’ve reduced the amount per batch to 250ml.¹ I use an ordinary canning jar. I certainly don’t sterilise the jar and I inoculate with only a teaspoon of yoghurt. Then I put the jar into a wide-mouthed vacuum flask and leave it. Eighteen hours later, give or take, yoghurt.

A couple of years ago I started making kefir too, which is even easier. Tip the kefir culture into a sieve over my bowl of oats and gently encourage the kefir out of the sieve, leaving the grains behind. Tip the grains into the jar, not even washed, let alone sterilised. (I do wash it roughly once a week, every 4–5 batches.) Add 250ml whole milk straight from the fridge. Cover with cheesecloth held in place with a rubber band and leave for 24 hours.

Almost all our yoghurt and kefir we eat at breakfast, usually with oats. Generally one batch of 250ml serves for two breakfasts. Occasionally I will use yoghurt in recipes, sometimes for bread, sometimes an Indian-style marinade or dish. In the summer I might strain a batch of yoghurt and eat that for breakfast with honey, no oats. When I do, I drink the whey.

So now, like Brent, lets do the maths.

It All Adds Up

A litre of whole milk is €2.19 at the local supermarket. The price is higher in the local bar where we usually get milk, but I’m going to use the supermarket price because the bar doesn’t sell yoghurt or kefir. Yoghurt is €1.69 for 500ml. Not counting the cost of fuel, or the capital of the jar and wide-mouthed flask, my yoghurt comes in at €0.55 a batch, €0.59 less, saving me 35%.

As Brent says, a no brainer.

For kefir, the numbers are quite a bit better. The supermarket has 320ml for €1.49. Mine costs about €0.74 for the same amount, saving me €0.75, a smidge over 50%.

I’ve never measured the yield of strained yoghurt, but taking Brent’s suggestion of 25% by volume, homemade Greek yoghurt would be €0.55 for about 60ml. In the supermarket, it is €1.65 for 150ml, so I am saving only 18%. But the whey I strain off is not wasted, nor do I have to pay anyone to take it off my hands.

Bottom line: I will continue to ferment my own milk, and continue to explore other products, such as calpis and kefir cheese.