The professor explains two effects that would slow down the bacteria growth and prevent the food spoilage. First is the temperature. The professor gave an example about the fresh fish. If we put fresh fish under the sun, it would spoil very quickly. Instead, if we put fresh fish in the fridge, it can keep it longer. This is because warm temperature was helped the bacteria to grow. Second is the moister. The professor gave an example about a regular liquid milk and powdered milk. She says that the powder milk would preserve longer than the regular liquid milk. This is because there's a difference between the water content. If the water is more in the food, it can be easily boiled. That's how the professor explains these two effects.
