Those questions are popular, but the answer …
Let’s start with the basics. What yogurt is? This is fermentation of milk triggered by three factors,
Milk or the lactose in the milk, which actually is a food for lacto bacteria (this is the second factor here). Those kinds of bacteria are called ‘’lacto’’ because their food is milk(''lacto'' derived from Latin).
Temperature is the 3rd factor. The temperature between 40 and 45 degree Celsius is the best temperature for activation of yogurt. That temperature induces rapid grow and multiplying of the bacteria.
The temperature is not a some special temperature, almost all bacteria, all good but also bad ones prefer this temperature, so please make sure that utensils which you are going to use are bacterial clean as simply pour very hot water over them before use.
At 40-45 degrees Celsius bacteria are awaken for new life and as usual after long sleep they need good amount of food. The increased numbers of bacteria eat and convert more and more lactose, thicken the solids until the lactose is over and they die or temperature drop and they go to sleep again. In light of this information please allow enough time bacteria to grow.
What else can stop the process of bacterial growth and multiplying? This is something which people don’t realise but this is the milk. All dairy milks should be whole as semi skimmed or skimmed milk are deeply filtered as small or big part of lactose and fat contents been removed. In those milks the amount of lactose might be not enough to support increased number of bacteria.
Historians’ thing that long time ago before 5000 years and even beyond the first yogurt been created naturally by spontaneous fermentation of milk and bacteria and that time filtered milks have not existed.
The second factor which can spoil you yogurt work is hidden again in the milk contents and this is amount of additives and preservatives. Their purpose is to kill all bad bacteria in the milk as well to improve some aspect as taste or texture or something else. The problem here occurs when you add good bacteria, because they will die killed by preservatives. The preservatives do not make difference between good and bad bacteria at all and by the way the yogurt bacteria might not like the taste of the additives so please avoid those entirely prior to mixing and pick up milk without any of those above. This move will save you money because almost all dairy milk brands with no preservatives are most popular, cheaper and with short shelf live.
Vegan Yogurt is also important topic, Is there vegan yogurt – the answer is no, but there is vegan substitute of yogurt.
By definition yogurt is a dairy product made by fermentation of milk and Lactose loving bacteria. Vegan substitute of yogurt is made from plant derived elements. They are called milk because some of them physically look like dairy milk but their chemical structure are not as dairy milk with small exceptions. When we prepare vegan substitute for yogurt we have to keep in mind that we have to mix the lactose loving bacteria with something which does not have any or enough lactose to support their growth, so they will convert only the amount of lactose in it.
But what is lactose – this is kind of sugar derived by galactose and glucose. When the bacterial culture eats it they broke down the lactose to those two sugars in this way simply said the yogurt is easy for absorption from the body than milk. We mention here some sugars because they are important part of making vegan yogurt. Warm slightly the vegan milk and add small amount of sugar, mix well and incubate. That sugar will replace in some degree the lack of lactose or bacterial food for the bacteria and they will have something to eat during incubations. As the bacteria convert lactose and thicken the solids and because there are no much solids in the plant derived milk the yogurt substitute will result in product with in some cases grainy texture and excess liquid, much more than those made with dairy milk. So please note that the amount will be less than the amount of the milk you used.
At this stage refrigerate the substitute and strain the liquid.
At the end it should look like this if it's made from soy milk
What vegan ‘’milk’’ we recommend. The best result you can get using soya milk. What about the rest of the vegan ‘’milks’’. Yes they work, but please make sure that the fat content is high and again there are no any preservatives and additives inside prior to mixing with yogurt bacterial culture. The best result you can get from homemade coconut milk, also homemade almond milk. In this way they will not be artificially filtered or diluted as well there will be enough fat contents and solids and will supply the bacteria with more solid base for their growth.
Very important – In case you wish to achieve the texture and quantity of the commercial vegan yogurt you need to use the same substances and thickeners like the commercial manufacturers.
For more info Please visit : www.yogurtathome.com