My mother never bought yoghurt in India while I had always been buying yoghurt in the UK. I was sort of okay with that until I realised how much waste I was creating and as we eat a lot of organic yoghurt at home, it was also costing us. So I looked at how I could make yoghurt at home. Googling the topic I came across yoghurt makers, yoghurt cultures, thermometers and many other things that I need to buy in order to make yoghurt. But I wondered how I could make yoghurt without buying any gadgets, like my mother did? So I did some research and here is what I do. I use my senses- eyes, touch and nose rather than gadgets to create this yoghurt.
The most important thing is the temperature of the yoghurt while setting- the starter culture of live bacteria need a incubation range of 110°F to 115°F or 43° to 46°C. Most yoghurt makers say that you should check this temperature with a thermometer. But what if you did not want to buy that either? I read that skin starts to form on the milk at 113° to 122° F(45° to 50° C) when it is heated. So what I do is heat the milk and wait until the skin forms. Then I remove the skin and wait again for about 5-10 minutes. (I can test the milk temperature by putting a drop on my palm. If it is just bearably hot, then it is above my body temperature of 98° F or 37° C). But I find that removing the skin thrice in about 5-10 minutes does the trick.
I mix about 60 grams of organic yoghurt (I use Yeo valley yoghurt but there must be equivalent in other countries) with half litre of the warmed milk. I then place the container in a wooden box and cover with blankets and towels. I also use an insulated glass panel found on the street, to cover the top. About four hours later, the yoghurt is ready. Make sure your container is clean and freshly washed, otherwise the milk will curdle when heated. People who have had my home made yoghurt say it is delicious and my children do not want to eat shop bought yoghurt again! You can keep aside a bit of the yoghurt to make a starter culture for the next batch of yoghurt but after awhile you will need to purchase a small amount of shop bought yoghurt again as the culture starts to get ‘diluted’ with use.
Cost of buying 1 kg organic yoghurt= £2.75
Cost of making 1 kg organic yoghurt by my method= about £1.28 (assuming 1 litre=1kg and taking into account some heating and the price of the bought yoghurt). Plus no waste. If not using bought yoghurt, then the cost would similar to the price of 1L milk from Tesco, i.e. around £0.97/ L
The yoghurt is ready!