The diagram shows how yogurt is made in a factory. Overall, there are seven steps in the process, starting from heating the milk and finishing with sending the yogurt to shops by truck.
First, raw milk is heated in a big pot up to 80°C for 30 minutes. If you heat it for more time, the yogurt will be thicker. Second, the milk is cooled down to 43°C. After that, in the third step, some live bacteria are added into the pot of milk.
Next, for the fourth step, the mixture is kept at 37°C for 4 hours. Then, the yogurt is put into a fridge to cool down in the fifth stage. In the sixth step, they add sugar and strawberries to give it flavor. Finally, in the seventh step, the yogurt is poured into three cups and then a big truck takes it away for distribution.
In conclusion, making yogurt needs many steps and we must control the temperature carefully at every stage.
