Yoghurt is a favourite dairy food - and with good reason. Nutritious, a great source of
calcium, low in fat and available in a huge range of flavours, yoghurt is great for the
whole family! Soft, smooth yoghurt is made when two particular bacterial cultures are
added to milk at a constant lukewarm temperature. Family members who are lactose
intolerant are able to enjoy yoghurt as the lactose is broken down by the bacteria.
Yogurt, also spelled yoghurt or yoghourt, is a favorite breakfast, lunch, or snack food found in the dairy aisle of the grocery store. A thick, custard- or pudding-like food, yogurt is made by the natural bacterial fermentation of milk.
There are several different ways to make yoghurt - from using an ordinary wide mouth
thermos, to using yoghurt starter kits (from supermarkets), or electric yoghurt makers
(available from department stores).
To make yogurt, warm milk is fermented or cultured with two types of bacteria -- Lactobacillus bulgaricus and Streptococcus thermophilus. Although many bacteria can make you sick, these bacteria are beneficial. They can help break down the lactose (sugar naturally occurring in milk), making yogurt more digestible than milk for people with lactose intolerance.
To make yoghurt in other way, warm one litre of fresh (pasteurised), UHT (long-life) or soy milk in a saucepan. Thoroughly stir in ¼ cup of milk powder and bring gently to the boil. Remove from heat and allow to cool until lukewarm (about 45oC). If using a thermos, ensure it is airtight and pre-warmed. Put two tablespoons of fresh commercial natural yoghurt in thermos base and mix in the milk mixture. Commercial yoghurt is used
because it contains the two essential bacterial strains needed to start the yoghurt
reaction.
Screw the lid of the thermos on tight and put in a warm place (wrapping in a towel
will help to keep the temperature constant). Leave for at least six hours - do not to
move the thermos at all during this time otherwise the delicate yoghurt curd will be
disturbed. Using a yoghurt maker can help to guarantee perfect yoghurt every time
because keeps the mixture airtight and at a constant temperature, but I find that if you
are careful a thermos will do the job.
To get a thicker yoghurt with a stronger taste, leave the mixture incubating for longer
(up to 12 hours). Once made, store the yoghurt in the fridge - it will keep for two to
three days. It is important to make sure all equipment is washed thoroughly and
sterilised in boiling water to prevent any undesirable bacteria from growing in the
incubated milk.