There are always times when food is scarce and also when they are in abundance.
Here is the problem.
We tend not to utilize all of the food when it is in abundance which causes them to spoil.
It is a shame because expensive food is laid to waste. Our ancestors knew this, and this is the main reason why they started to preserve food.
Food preservation is not that hard, and I will list over twenty different methods that can be used.
Some of the methods can only be used at scale by food factories, while you can use some of the other techniques at home.
Preservation is also critical for prepping which is the main reason why I have written this article.
How Spoilage Occurs
Spoilage occurs when there are chemical and physical changes to food which makes it unfit for consumption.
The process can come from microbes, enzymes and also insects. The food will start to taste off and will naturally degrade.
The three most common types of microbial spoilage come from bacteria, mold, and yeast. In this section, I am going to go over each one of them.
Most living organisms will have bacterial cells living between their own. Once this residing organism dies, the bacterial cells will start to reproduce to get rid of the living matter.
There are many factors which can control the growth of these bacteria and include pH, moisture, oxygen, and temperature. If you can control any of the factors mentioned above, you can inhibit bacterial growth.
- Controlling the pH. Bacteria need an optimum level pH which is not too acidic or alkaline for them to survive. If you can add acidic or alkaline agents to the food, then it can potentially prevent spoilage.
- Moisture. Bacteria also need moisture to survive and reproduce. If you can dehydrate the food to get rid of the humidity, the bacteria will not survive. Adding salt and sugar can also reduce the moisture availability to the microbes.
- Oxygen. All aerobic bacteria need oxygen to survive. If you can remove the oxygen with methods such as canning or vacuum packing, you will slow down the spoilage process.
- Temperature. All living organisms can survive inside of a very narrow range of temperature. You can disrupt this range by cooking the food or freezing it.
Mold and yeast can be classified as fungi which can contaminate food with the help of spores. The spores will flourish especially if there is enough sugar and if the pH is slightly acidic.Yeast love to grow on fruit, vegetables and also bread.
Some of the chemical reactions that can cause the food to degrade are oxidation and the Maillard reaction.
Oxidation is when oxygen molecules along with free radicals cause unstable reactions inside the cells of the food.
Fats and lipids are especially vulnerable. When food becomes oxidized, it will develop a rancid taste which is not favorable.
In this section, I will discuss the different methods which can manipulate the temperature of food which will stop the growth of unfriendly bacteria and the activation of enzymes which contribute to food spoilage.
By freezing the food, you will lower its temperature to such an extent where the bacteria will not grow anymore. Freezing might not kill all of the bacteria, but it will stop them from reproducing.
Foods that you can freeze:
- Leafy greens.
The only drawdown is that the food that you want to freeze needs to have the right amount of moisture content to do so. To counter this problem, you can blanch the food by placing it in boiling water for a minute or two and then placing it in cold water to stop the cooking process. After this blanching process is done, you can put it in the freezer.
The blanching process will also kill most of the bacteria which will reduce the growth further. It is also essential to freeze the food as fast as possible.The reason for this is that the slow freezing methods allow for the growth of large ice crystals which will rupture the wall of the cells which causes the food to become soggy once defrosted.
During the ancient times, people had to bury their food below the snow to freeze. Today, we have the luxury of using fridges and freezers.
Pasteurization happens when food (mainly liquid) is being boiled to such an extent where it kills most if not all of the bacteria and microorganisms.Foods that you can pasteurize:
- Fruit juices.
One of the most significant drawbacks of pasteurization is that it sometimes destroys the nutrients and friendly bacteria inside the food. It also affects the taste of the food.
Maybe you can agree with me.I am not a big fan of pasteurized milk such as long life milk because it tastes like plastic. I can still remember the good old days when we poured ourselves milk which came from a Jersey cow.
We poured it from steel containers where the milk stood in a large freezing room. You had to be careful because it was so cold that you got brain freeze. The duration and temperature of the pasteurization process will vary depending on the pH of the liquid. The lower the pH, the less heat is required to kill most of the pathogenic bacteria.
Some biologists also believe that pasteurization kills all of the friendly bacteria as well. This problem might contribute to the large scale problem of dysbiosis.
Canning And Jarring
Canning food for preservation is another excellent method that you can use from home. This method of food preservation became very popular during the early 1800s.
Foods that can be canned or jarred:
- Any meat.
The process makes use of two methods to preserve food. The first method is by boiling the food inside the can which kills almost all of the bacteria. The second method is then to seal the can while it is still hot so that it will create a vacuum. The sealing method will make sure that the already sterile food will not be contaminated down the road.
Only after opening the lid of the can, will bacteria start to enter the can. It is also known to “can” food inside a glass jar.
Most people at home will can their food with a glass jar either with water bathing or pressure canning. Most high acidic foods such as fruit can be jarred with the help of water bathing.
Foods such as meats and most vegetables are low in acids and need to be pressure canned to create a more powerful vacuum.If the canning process is not done correctly, the food can becomes contaminated by Clostridium botulinum which can cause botulism.
The word confit comes from the French term “confire” which means to preserve something. The most common types of confits are meat and fruit confits.
Types of food:
A confit is made when meat is salted and then slowly cooked at a lower temperature in either their own fat or lard. The meat will then be left in the fat until it gets cold. The fat will become solid and act as a protective layer over the meat.
The most common type of meat used in confits is chicken legs. Meat confit will generally last for a couple of months up to a year.
The slow heating process will kill almost all of the pathogens that might live on the meat and cause spoilage later on. This method of preservation was used in Europe especially France before the development of freezers.
Drying & Salting
Microbes need a moist environment to survive which is why drying the food is a plausible way for food preservation. Think about foods such as jerky, pemmican and also dried food as an example. Microbes can also not live in an environment that is too saline, and salt also can dehydrate foods such as meat.
Using A Dehydrator Or Sunlight
Microbes that cause spoilage need moisture to survive, and if you can take it away, it will prevent their population from growing. Drying food also intensifies the flavor and makes it less bulk so that it can be stored easier.
The best food for dehydration:
- Thinly cut meats
To make the process faster, you can get your hands on a dehydrator which will draw the moisture from the food. If you are familiar with crop farming, then you will also know that the crop needs to be dried out on the land before harvesting. If you harvest it when it is still wet, it will spoil inside your bunkers or silos.
You can also buy dried milk or egg powder from the grocery store. During earlier before dehydrators, our ancestors used the sun to dry most of their food. They cut their meat in thin strips and dried it in the sun.
They also dried fruit in the summer month to provide for the winter. My grandparents used to have a small piece of land where they had an orchard. They grew over five different species of peaches, apples, grapes and also figs. My grandmother used to dry the fruit; otherwise, it all will go to waste.
Freeze drying is one of the most effective methods at removing almost all of the moisture. The difference between this method and conventional drying is the temperature and state of the moisture.
Products that should be freeze-dried:
- Biological pharmaceuticals.
Conventional drying methods require the moisture to evaporate by applying heat and drier air. With freeze-drying, the temperature of the moisture must be low enough for it to become frozen.
The frozen food will then be placed in a strong vacuum where the solid ice will start to sublimate (turns from solid directly to vapor). Freeze drying is very sought after because it keeps the original structure or shape of the food. This method also does not change the taste or nutrient value of the food.
All you need to freeze dry your food is to freeze them and place them in a strong vacuum until all of the moisture has escaped.
The smoke itself has antimicrobial effects which will prohibit the growth of microbes on the surface of the meat. It also has antioxidant properties which will prevent oxidation.
Some of the foods that can be smoked:
- All types of meat.
The only problem with smoking is that the smoke alone is not enough to preserve meat. The smoke cannot penetrate deeply enough into the meat. The meat needs to be salted or dried, and the smoke only adds an extra layer of protection against bacteria.
You can smoke any meat which include fish, chicken, steak, brisket and also lamb. I have once eaten smoked pork ribs which are to die for.
The type of wood that you use to smolder the fire will add a different flavor to the meat.The only concern around smoked meat is that if you consume too much of it, it will increase your risk of developing cancer.
Salt does not only enhance the flavors of food but will also increase the osmotic pressure inside of the food which will take the moisture away from the bacteria.
Most common meats for salting:
- Salted pork.
- Salted Cod.
Salting can be used in almost any types of meat which include pork such as gammon, fish, beef, and lamb.It is very well known for jerky to be very well salted and dried to give it a longer shelf life. Salt is also a significant component of curing meat which is also a preserving method.
Salt has been used to preserve meats for a very long time but needs to be combined with other methods to work effectively.Salt is commonly used with drying which will lower the moisture content substantially.
Pickling is another preservation method that makes use of salt and acid especially for preserving fresh vegetables.
- Green beans.
You can preserve almost any type of vegetable, and I have also eaten pickled fish combined with curry and onions.
I order to make it, you need to cook the vegetables first until it is cooked through. You can make use of sterile mason jars to store the cooked vegetables inside brine mixed with vinegar and some spices.
The salt along with the vinegar makes it unfavorable for the bacteria to grow inside the jar. You can also make use of canning to preserve the food further.
Some people also like to add some yeast instead of the vinegar to create lactate which will lower the pH to prevent other bacteria from growing.
Biological preservation is when organic chemistry is applied to preserve food. Examples include fermentation, flavonoids, honey, etc. Most of these methods can also be used at home.
Consuming flavonoids is not only good for your health, but it can also be used as a preservative. Flavonoids have powerful antimicrobial and antioxidant properties that will help to preserve food.
- Fruit juices.
Flavonoids are a naturally occurring phytonutrient that comes from most vegetables and fruit. Flavonoids are responsible for the color of fruit and vegetables.
It is also stated that this natural preservative is more effective than commercially used ones. It also does not have some of the unhealthy effects that come with synthetic preservatives. Some of the most common preservatives used are aspartame and nitrates which has the potential to cause cancer.
Even though this chemical is not yet used on a larger scale, there is a shift in the development of the synthetic version which can be mass produced. There is some potential in exploring this new type of preservative for large scale use.
Bacteria need oxygen to survive, and if we can reduce the oxygen in the food with the help of antioxidants, then we can reduce their growth.
- Dried fruit.
- Alcoholic drinks.
- Butter & margarine.
Antioxidants act as scavengers to get rid of the oxygen molecules which can lead to food spoilage. Have you ever noticed the brown color on the flesh of a peeled apple? This browning in color happens because the skin is not available to help protect the flesh of the fruit from oxygen.
The four most common antioxidants used in food are citric acid, butylated hydroxyanisole (BHA), ascorbic acid (vitamin C) and tocopherols.Oxidation occurs especially in lipids such as fat and oil. Products such as margarine and sunflower oil make use of BHA which stops the breakdown of fat caused by oxidation.
Ascorbic acid and citric acid is mainly used in canned and dried fruit, beer, jams, and alcoholic drinks.
In most cases, you want to avoid the overgrowth of some bacteria in food, but sometimes, you can stimulate the growth of desirable bacteria that can help in preserving the food.
Most common foods used:
Fermentation requires a bacterial culture and sugar to produce alcohol and carbon dioxide. The most common culture used is from lactobacillus which creates lactic acid.
This is the reason why most fermented products have a sour taste to them. The lactic acid will lower the pH of the food which will prevent the growth of harmful bacteria.
The fermentation is very old and is still used to make alcohol and as a preservative. The fermentation process will also use all of the available oxygen. Products that are fermented also helps to balance the natural microbial diversity in our digestive tract.
What if you could use microbes that hunt for disease-causing bacteria in food? A Bacteriophage is a type of virus that infects bacteria which will ultimately destroy them.
The food used.
- Ground beef.
There is a long list of harmful bacteria in food that can be harmful or result in food spoilage. Some of the most common bacteria that can be targeted by bacteriophages are Salmonella, Escherichia coli, Listeria, Campylobacter, and Botulinum.
It is essential for the virus not to target our cells and only target that of the bacteria that are harmful. How nice would it be if we can store food without having to use a freezer?
Honey does not only taste good but can also be used as a preservative. It has antimicrobial properties and will also help draw out some of the moisture.
You can use honey in the following foods:
- Mostly fruit.
- Sometimes meat.
In history, people would lay their fruit and sometimes meat in honey which helps to preserve the better. Honey is also one of the best natural preservatives you can find today.
It is also known for honey to ferment once it is diluted with water which is not advised. The high concentration of sugar draws out most of the moisture through the process called osmosis. During ancient times, honey was diluted to create alcohol beverages such as honey beer called mead.
Air manipulation involves the change in pressure in and around the food. This change in pressure has the potential to kill living bacteria and also to remove all of the oxygen it lives on. The oxygen removal will also reduce oxidation.
Pascalization is the process which food goes through when they undergo very high pressure which kills the bacteria and also preserves the food.
Pascalization can be used in the following foods:
- Dairy products.
- Vegetable and fruit smoothies.
Most of the organisms such as E Coli and Salmonella will be killed when more than 400 MPa is applied to them.
This process also does not change the taste, color or flavor of the food. It might change the texture which is why mostly liquid type food is used.
The food will be filled in a steel chamber which will then be filled with water. Pressure will then be applied until all of the microbes are killed. This procedure does not include any chemical additives or preservatives which is ideal for people that want to go more organic and chemical free.
Vacuum sealing is when food is placed inside a plastic bag, and all of the air is sucked out before sealing.
Foods for vacuum sealing:
- Most meats.
The advantage of this method is that it can be used on almost any type of food. The oxygen-containing air will be sucked out which will prevent further bacterial growth.
This method alone will help your food to last up to five times longer but needs additional treatment for it last longer than a couple of days. The food can either be salted or dried (or even both) before it can be vacuum sealed.
By vacuum sealing the food, you will also make better use of the limited space because it will reduce the volume of the food by sucking out the air. The airtight plastic will also protect the food from frost burn which comes from the freezer.
In this section, I will cover radiation, electroporation and the use of blue light to help preserve food.
When beams of electrons are fired into food, then it can be referred to as nuclear radiation or just radiation.
- Mostly fruit and vegetables.
- Can also be used for meat.
When most people hear the word radiation, they think of cancer treatments and nuclear warfare. The majority of people does not even know that it can also be used for food preservation.
The most common source for radiation is Cobalt. First, the food will be sealed off with plastic and then vacuum sealed to prevent any bacteria from contaminating the meat, and then it is radiated. When radiation comes into contact with bacteria, it will change its DNA which will result in its death.
Some of the drawdowns are that fatty foods will become rancid after it is radiated. Radiation also has an adverse effect on some of the vitamins.Most people also have a problem when it comes to radiation, so this method is not widely common.
This method makes use of two electrodes which will generate a pulse between the food which will kill the pathogenic bacteria.Food used:
- Mainly fruit juices.
The electrodes will emit a strong pulsed electric field (PEF) will open the pores of the cell membranes which will result in the death of the bacteria. It is good because the liquid does not need to undergo heat treatment which might preserve some of the nutrients and taste.
It does not have any effect on product quality. This process has passed the HACCP test for food quality and safety. This process is still in its infancy and requires a lot of fine-tuning to be more effective at a larger scale. One significant drawdown is the amount of energy needed which can be costly at the end.
Light from blue LEDs have the potential to eliminate bacteria and some viruses in food that can cause disease and for it to spoil.Foods used:
- Acidic fruits.
- Cooked meat.
During the search for chemical-free food, scientists have discovered that a particular blue wavelength can kill pathogens inside food. Blue light has an antibacterial effect which can trigger photosensitive components inside the cells of bacteria which will inevitably cause them to die.
The temperature and pH levels of food will affect the efficiency of the blue light on bacteria. When the pH is neutral, the light will not effectively eliminate the bacteria. Only when the pH is slightly acidic or alkaline, will the blue light have an effect.
The three main strains which can be eliminated are Salmonella, E Coli and Listeria.This method will also not harm the taste and nutrient quality of the food.
Organic And Inorganic Chemicals
The most popular method used by factories at a large scale is the use of chemicals which inhibits bacterial growth and sometimes stops oxidation. They might not always be very healthy but are cost effective and practical to use.
Below is a list of some of the most common chemicals used:
- Sodium Nitrite. This molecule fights harmful bacteria that can cause disease and spoilage. It is mostly used in meats such as salami, polony, some fish, etc. It gives meat and pinkish red color which is desirable. The only drawdown is that it is carcinogenic which means it can cause cancer.
- EDTA. Mostly used in the medical field for heavy metal chelation, it can also be used as a preservative. It has a white crystalline appearance which has a slightly salty taste. It is used in most foods and can be carcinogenic when transformed into benzene.
- Sulfites. This molecule is a type of salt that contains the sulfite ion. They occur naturally in wine and is mostly used in dried fruit, potato chips and also some alcoholic beverages.
- Sodium Benzoate.
- It is a white powdery substance that can be used as a preservative. It is best used in acidic foods such as fruit juices, toppings, fizzy drinks, etc. It causes anaerobic fermentation around bacterial cells once absorbed which causes its death.
Today, I have given you several ways to preserve your food. Food factories explicitly use some of the methods. Some of the methods included in this list can also be used at home.
What was your favorite method?
Please leave a comment below and tell us why