How to Make Yogurt at Home

Step-by Step Tutorial

To enjoy yogurt, you must have whole milk first and a right starter, which is actually a blend of yogurt bacteria. For this, any kind of milk will do. Cow, sheep, goat, even buffalo milk is more than perfect for making yogurt. Yogurt is made through a process called fermentation, which will modify the structure of the milk. The fermentation of the milk takes place when the good bacteria in the starter trigger fermentation. Please be careful as not every brand of milk can supply the right set of nutrients for bacteria, but any bacteria can thrive in the perfect environment, which you'll need to create. If you want to enjoy yogurt at home, here are a few easy steps to follow.

Pick up carefully your base products – whole dairy or soy milk with no additives and preservatives.

• Boil the whole milk first. This will kill all kind of non-yogurt bacteria in it and evaporate the water in the milk.
• Cool the milk down to a lukewarm state in order to start the fermentation process. Somewhere between 40 and 45 degrees Celsius is the ideal temperature, which will make the bacteria thrive and start producing your yogurt. Just touch the container with the milk and if you feel it ''warm'' this means that the temperature is ideal.
• Introduce the bacteria, with the help of the starter, into the milk and stir gently.
• Next, allow the milk to sit in a warm and protected place, without bothering it for a while. During this time, the bacteria will work and will process nutrients, and will separate the milk's sugar, called lactose, into simpler components for easy absorption by your body. Lactic acid is also produced meanwhile, which gives the yogurt its well-known acidity.
• How long will the incubation takeThe term depends very much on the met conditions, so it can be finished overnight or it may take another day. The time for incubation varies and depends on the used milk, yogurt-making appliance, although it should not take more than 24 hours if you use starter and milk, and will take just 3-6 hours if you use ready yogurt as a starter.
• Make sure to check the yogurt and see when it has the consistency you desire. Still, do not allow the yogurt to ferment for more than 2 days because it can get way too sour if the bacteria multiply too much.
• Once the fermentation process is complete, make sure to store it in the fridge, so you will stop the bacteria from multiplying and ruining the taste of your yogurt. If not stopped by a cooler temperature, the bacteria will continue consuming the milk, until its food source is depleted, which explains the spoiled taste yogurt can get or the visible separation of the milk.

Also, don't forget to reculture the next batch of yogurt with 2 or 3 spoons taken from the existing yogurt, for every litre of milk, so you can enjoy yogurt as much as you like. Do remember that re-cultivations made by using ready yogurt and milk need 3-6 hours of fermentation only as the quality in terms of texture and taste are even better.

As you can see, it is not rocket science to make yogurt at home. There are just a few simple rules to follow in order to enjoy yogurt as much and as often as you please.

Enjoy

Do you know...

In the year 1905 Stamen Grigorov made his famous discovery of the causative agent of the milk fermentation. His scientific advisor Prof. Massol immediately wrote a letter to Prof. Ilya Mechnikov at the Institute Pasteur, Paris: "Persistence and tenacity in the scientific work and research are distinguishing features of my Bulgarian co-worker and assistant Stamen Grigorov… After a number of successive experiments, he was able to discover and isolate the causative agent of Bulgarian yoghurt. Your work is inspired by the striving to discover a mean to increase the human life longevity. Besides your remarkable "phagocytes" you should think about the Bulgarian yoghurt and this rod-like bacillus discovered from Stamen Grigorov, which I have also observed microscopically. It might be useful for your studies.".

During his investigation, Stamen Grigorov discovered two more bacterial species: streptobacillus and micrococcus - Streptococcus thermophilus. They co-exist with the lactobacilli in Bulgarian yoghurt in natural symbiosis.

In return to the Prof. Massol's letter, Prof. Mechnikov sent immediately an invitation to Stamen Grigorov to visit The Institute Pasteur. In the big lecture hall there, Stamen Grigorov reported the discovery of the lactobacilli. For scientific demonstration, he brought with him Bulgarian yoghurt and a microscope. The direction of Pasteur Institute entrusted Prof. Mechnikov with the task to confirm independently the discovery of Stamen Grigorov and to report the results to the Scientific Council of the institute. Three years later this resulted in a scientific publication: "Some notes regarding the yoghurt" printed in Les Comptes rendus de l'Academie des Sciences, 1908. Soon afterwards Coendi, Mikelson, Luerson and Koen, Mechnikov's scientific assistants, named the microorganism discovered by Stamen Grigorov ''Bacillus bulgaricus'' or "Bulgarian milk bacterium".

Mechnikov explained the exaggerated life longevity of Bulgarians with the beneficial health effects of Bulgarian yoghurt.

Nowadays under the designation "Bulgarian yoghurt" one understands fermented milk products, obtained as a result of the activity of symbiotic culture of Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus. The lactic acid fermentation, caused by those two bacterial species, induces profound changes in the milk content. The fermentation products exhibit positive health effects on the human organism. Scientific investigations demonstrated that yoghurt consumption influences positively the balance of the microbial population in the human intestine. It facilitates the assimilation of lactose and stimulates the immune system. Metabolites produced by Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus during the fermentation process lead to increasing of the cell counts of healthy and beneficial intestinal microorganisms.