The students first visited the school kitchen where the cuisine teachers showed them the different types of food products that they use (freshed, tinned, frozen, vacuum preserved, etc.) and the need to make sure that all the products are safe to be eaten and preserved in the best conditions.
After that, the students went to the science lab with their science teacher and the English teacher to get to know more about microorganisms and the importance of preserving food with different methods (frozen, diluted saline solution, concentrated saline solution, sodium nitrite, vinegar). The students practiced in the laboratory different methods to preserve food safely. They observed the chemical reactions, they checked the temperatures and they observed how microorganism reproduced and what conditions they needed to reproduce. That way they learnt how to preserve food safely.
Though experimentation and direct observation the students obtained some results that were later analysed. Then they wrote their conclusions.