Conditions for mold growth

Mold is a microorganism and although it is one of the smallest living beings, in the process of life activities there is a close relationship with the surrounding environment. The growth of mold depends mainly on the four living conditions: nutrients, oxygen, water and temperature.

1) Nutrients

Mold has the law of vital activity that organisms in general have, they need to constantly absorb nutrient material from the external environment and make use of it, get from it the energy they need to carry out the vital activity they need, synthesize new cellular material. Molds, like other living things, are made of carbon, hydrogen, oxygen, nitrogen and other chemical and mineral elements, in the process of their growth and reproduction, it is necessary to continuously absorb the necessary nutrients from the external environment, such as carbon, nitrogen, inorganic salt, auxin, etc.

2) Oxygen

There are mainly two kinds of aerobic mold and facultative aerobic bacteria, among which aerobic mold must be in the aerobic environment to grow and reproduce. Some foods are often placed in the “Oxygen Absorber” to make the food packaging environment in an anaerobic state, thereby destroying the necessary condition for mold growth and reproduction, so as to achieve the purpose of extending the shelf life of food.

3) Water

El agua es el elemento nutritivo más básico para los mohos, las células de moho contienen mucha agua, el contenido de agua es de aproximadamente 85% ~ 90%. La propagación de microorganismos como el moho está estrechamente relacionada con el agua, cuando AW (Actividad del agua) <0,64, no puede crecer ningún moho.

Dry environment is not good for the growth and reproduction of microorganisms, drying may cause cells to lose water, increase intracellular salt concentration or denature proteins, microorganisms will gradually die under dry conditions. Therefore, some products we often use “Moisture Absorber” or “Desiccant” to make the environment in food packaging dry, destroying the necessary conditions for the growth and reproduction of mold, in order to achieve longer product preservation.

4) Temperature

The temperature range required for the growth and reproduction of various microorganisms is different. The adaptation temperature range for halophilic microorganisms is below 20℃, the spoilage of refrigerated food is mainly caused by these microbes. The temperature range of medium temperature microorganisms is 20~40℃, and most microorganisms in nature belong to this category.

High-temperature microorganisms adapt to a temperature range of more than 45℃, such as microorganisms in hot springs. Mold on ordinary bread and other foods belongs to medium-temperature microorganisms, so these foods can be stored in the refrigerator to extend their shelf life.

Through the above introduction, we know that the growth of mold mainly depends on nutrients, oxygen, water and temperature, which are the four main living conditions. During the transportation, storage and shelf life of products after leaving the factory, nutrients and temperature are two factors that cannot be controlled artificially.

Therefore, the quality of food and products is mainly controlled by “oxygen absorber” and “moisture absorber”. The former controls oxygen and the latter controls water. All kinds of food should use “Oxygen absorber” or “desiccant” which should be decided according to the moisture content of the packed product.