Throughout history, humans have been able to preserve food with different methods.
- It may interest you: “Organic food: what they are, and 6 benefits of consuming them”
The 10 most common ways to preserve food
The basic reason why we have to use food preservation techniques is that we have to prevent other living things from eating our food. The main enemies of human beings in this sense are not ants or any other opportunistic insect or animal, but microorganisms.
Microorganisms spoil our food, but thanks to the food preservation techniques we have developed we can fight them . Below you will find the conservation techniques that inhibit its development.
1. cold
Today we come from shopping and the first thing we do is put a lot of our food in the fridge or freezer . Obviously our modern life could not be understood without these appliances, which have caused a real revolution in our way of living.
We practically lived through our entire evolutionary history without a fridge and freezer, but it is necessary to highlight that we have known the ability to preserve cold since ancient times. Our prehistoric ancestors already stored food in caves and glaciers to take advantage of its cold-keeping properties.
2. Fermentation
In fermentation, the human being takes advantage of the metabolism of fungi and bacteria . For example, some bacteria can consume milk sugar, lactose, resulting in lactic acid and a product we know as yogurt.
This benefits us in two ways, because in addition to lengthening the shelf life of a product like milk, we are able to enjoy another new food. Other examples are beer, cheese, kefir, vegetable pickles, fermented tea, tempeh, or miso.
3. Salting
Thousands of years ago it was already observed that salting certain foods could make them last for a long time . Salt causes the food to lose water, and together with the high concentration of salt, it prevents microorganisms from developing in such a hostile food.
This technique is known as salting, and once we want to consume the food that has been salted, we can desalt it with water. The final product acquires other organoleptic characteristics and is generally highly appreciated.
4. Herbs or plants
Parts of different plants have been used since ancient times to help preserve food . By itself it is not a very strong method, but in certain situations and combined with others like the previous one, a good result can be achieved.
Many herbs, roots, fruits or bulbs contain compounds that inhibit bacterial growth, such as: rosemary, anise, sage, turmeric, cinnamon, pepper, garlic, cloves, oregano, lemon, etc.
5. Dehydration
Dehydration is removing water from a food . Generally, the more water a food has, the easier it is for microorganisms to take advantage of it, so that we restrict their possibilities of proliferation.
An example is adding salt as we have seen, but there are more. For example, since our remote history the sun and wood ovens have been used to dry food. Today there are more modern machines for this.
6. Smoked
The smoking technique is also very old, appearing at some point after the mastery of fire. Food that comes close to a fire dries out due to the heat, so it loses water , but it also acquires unique characteristics thanks to the smoke.
The smoke provides a series of substances resulting from the combustion of wood that gives a very particular taste and flavor to food. It is a conservation technique that transforms the product.
7. Oil
Oil is also an ally for the preservation of our food , since bathing our food in it makes many microorganisms unable to thrive. The oil reduces the chance that aerobic bacteria can use the oxygen in the air to grow.
Even so, there are many anaerobic bacteria (that is, they do not use oxygen to carry out their metabolism) that can reproduce despite the fact that we store food in oil. It is for this reason that preserves in oil are combined with cooking in the packaging process.
8. Jam
In addition to removing water, adding sugar helps inhibit the growth of microorganisms . It is an inverse strategy, because if we add a lot of sugar to a product, there is less water. And also, as with salt, the high concentration of sugar harms bacterial proliferation.
Normally this preservation technique is applied to fruit, which can be preserved for months and years by transforming it into jam.
9. empty
To vacuum pack, what is done is that the air is removed and the food is much less exposed to oxygen. This greatly helps to stop the growth of aerobic bacteria, but anaerobic bacteria can continue to grow.
In general, packaging with plastic films allows you to gain several days when it comes to preserving a product. Normally the food can be stored in the fridge, combining the two preservation techniques.
10. Pasteurization
Pasteurization is a modern technique for preserving food . It generally consists of applying a large dose of heat (150ºC) to liquid foods in a matter of thousandths of a second, managing to kill many microorganisms.
After such injection of temperature, the product is hermetically packaged, managing to greatly lengthen the expiration date. Unfortunately this procedure also kills some microorganisms that can act as probiotics in our body.
- To learn more about probiotics: “Top 9 Probiotic Foods (and Their Benefits)”
Bibliographic references
- Fellows, P. y Hidellage, V. (1992). Making Safe Food. Londres: IT Publications.
To the classic question “what do you do?” I always answer “basically I am a psychologist”. In fact, my academic training has revolved around the psychology of development, education and community, a field of study influenced my volunteer activities, as well as my first work experiences in personal services.