Having the ability to preserve food is essential for living a self-sufficient lifestyle, be it in the case of emergencies, homesteading, or just wanting access to chemical-free, nutritious food.
For beginners, it can be difficult to know which method or technique to use with so many options available.
This guide outlines the common techniques for saving food for the long-term, including canning, dehydrating, freezing, freeze-drying, fermentation, salting and sugaring, and alcohol preservation.
Preservation methods address the causes of food spoilage–microorganisms, enzymes, oxygen, pests, and light–by helping to prevent or reduce their effects.
Gaining insight into these components will enable you to make smart choices when it comes to preserving the food that best suits your purposes.
Why Food Preservation
Methods of food preservation slow down the deterioration of food items, enabling them to remain edible for an extended period.
Preserving food has been a crucial part of human life for centuries and remains so today.
There are many reasons why food preservation is important, including:
Stockpiling emergency food for disaster preparedness
Natural disasters can occur without warning, so it is important to be prepared. Food preservation ensures you’ll have something to eat in case of an emergency.
Homesteading and keeping surplus
Growing and preserving your own food allows you to have access to an ongoing food source.
Through the preservation of food, one can utilize their surplus from the garden or a successful hunt; this includes canning vegetables and even smoking meat.
Food without additives and preservatives
Food preservation techniques like canning, drying, and freezing don’t need additives or preservatives. This ensures that the preserved food is healthier and safer to consume.
Saving money by buying in bulk
If you purchase food items in bulk when they’re in season, you can save a great deal of money. By preserving food, you can reap the benefits of discounted items and have a readily-available stash of food for later.
Personal satisfaction
Gaining knowledge in the art of food preservation is a beneficial skill that increases your independence.
It brings a great sense of satisfaction to know how to preserve food, thus being able to provide for yourself and your family.
We’ll go over several food save techniques to keep your food fresh, like canning, dehydrating, freezing, fermenting, salting/sugaring, alcohol soaking, vacuum sealing, oxygen absorbers, freeze-drying, and curing.
We will also discuss the importance of food preservation and explore five major causes of spoilage: microorganisms, enzymes, oxygen, pests, and light.
Factors that cause food spoilage
Food can spoil because of several factors, including microorganisms, enzymes, oxygen, pests, and light.
Microorganisms such as bacteria, yeast and molds consume food and produce wastes that give spoiled food a bad smell.
When oxygen and moisture interact with the natural enzymes found in food, it can cause it to spoil.
Oxidation, caused by oxygen, is especially damaging to foods that are high in fats and fatty acids.
Pests can contaminate food supplies, whereas light can cause deterioration of certain foods through photodegradation.
In order to keep food fresh and avoid spoiling, it’s important to understand the relevant factors.
Methods of Food Preservation
Food preservation techniques are used to keep food fresh and safe for a longer period of time, while also maintaining its nutritional value.
Food preservation is the act of keeping food edible for a longer period of time. Various food preservation techniques exist, each with its own benefits and drawbacks.
Canning
By heating food to high temperatures, canning eliminates bacteria and other microorganisms that cause spoilage.
The food is sealed in an airtight container, usually a can or jar, which protects it from further contamination.
Preserving food through canning is a popular choice because of its simplicity, cost-effectiveness and potential for being done at home.
Even though it can take some time and special equipment like a pressure canner or water bath canner, the process of canning is worth it.
Freezing
Another popular way of preserving food is by freezing it. By reducing the metabolic activity of enzymes and microorganisms, it can help to prevent food spoilage.
By freezing the food, it can be kept in a suspended state, thus preventing the growth of dangerous bacteria.
Freezing food allows for it to be stored for several months, or even years. However, freezing can lead to alterations in texture and taste, so it might not be suitable for all types of food.
Dehydration
Dehydrating food is a process of removing moisture, which can inhibit the growth of microorganisms and enzymes.
Dehydrating food can be done with a dehydrator, an oven, or simply placing the item in direct sunlight.
Dehydrated food can stay edible for long periods of time, but it must be rehydrated before consuming. Lack of hydration can result in a decrease of both flavor and nutrient content.
Vacuum Sealing
Vacuum sealing is an effective food preservation technique which removes air from the packaging to reduce the growth of microorganisms and enzymes.
Vacuum sealing entails the use of a vacuum sealer and specially designed bags.
Vacuum sealed food can be kept for extended periods of time, but should be put in the freezer or refrigerator. Special equipment is necessary for vacuum sealing, and it can be costly.
Oxygen Absorbers
Oxygen absorbers are components used in food packaging consisting of iron powder, salt, and clay to reduce oxygen levels and slow the development of microorganisms and enzymes.
The combination of Mylar bags and oxygen absorbers can extend the shelf life of food for up to 15 years and is a popular choice for long-term food storage.
However, these can be costly and may not function optimally in humid conditions.
Freeze Drying
Foods can be preserved through freeze-drying, a technique that involves freezing and then subjecting them to a low-pressure vacuum.
Freeze-drying slows the growth of microorganisms and enzymes, while preserving the flavor, color, and texture of food.
Freeze-dried foods can be kept for multiple years, but it is more expensive than other preservation techniques and requires a specialized appliance.
Curing
Food curing is a technique of food preservation through the use of salts, sugars, nitrates, and nitrites in order to remove moisture from the food.
Smoking can also be used as a curing technique to create an outer layer that is more difficult for bacteria to penetrate.
Curing is an ancient form of preservation, but it can be especially lengthy and requires the proper equipment.
Fermentation
For centuries, fermentation has been a popular food preservation technique in various cultures across the globe.
In order to produce lactic acid, acetic acid, and other organic acids, the process involves growing beneficial bacteria, yeast, or mold on the food to break down sugars and starches.
By incorporating certain acids into the food, it can act as a natural preservative and shield it from harmful bacteria and other microorganisms.
Canning
Preserving food through canning consists of heating it to a high temperature, sealing it tightly in an impermeable container, and keeping it in a cool, dark area.
Heating the food to a high temperature destroys any microbial or enzymatic contaminants, making it safe to eat for an extended period.
There are two types of canning — Water bath canning and pressure canning are two methods of preserving food.
Water bath canning is the best method for preserving high-acid items like fruits and pickles, whereas pressure canning is utilized for low-acid foods including veggies, meats, and soups.
Water bath canning consists of packing food in jars, attaching a lid and ring, and then boiling them for the set amount of time.
Boiling the water deactivates the microorganisms that cause food to spoil, allowing it to be stored in vacuum-sealed jars for up to a year.
Pressure canning is a more advanced technique that requires a pressure cooker to heat food at a temperature much higher than what water bath canning entails.
Low-acid foods need to be heated up to a higher temperature in order to destroy any potential bacteria like Clostridium botulinum that are capable of causing harm.
Before canning, it is important to properly prepare the food and the jars. The preparation process includes washing jars and lids, cooking or blanching the food, and adding the necessary amount of acid or vinegar.
Regardless of what food is being canned, it is critical to follow the applicable timing and pressure instructions.
Home canning is an effective way to preserve food, and it’s also a great way to make your own jams, jellies, and pickles.
Using the right equipment like jars and a canner, food preservation through canning can be done safely and effectively for long-term storage.
Dehydration
Food dehydration is an effective method of preserving food as it removes moisture, making it difficult for microbes to grow and deactivating enzymes.
This technique can be accomplished using a dehydrator, oven, or sun exposure.
Dehydrating is an ideal preservation method for fruits and vegetables, and it can also be used for meats and fish. Dehydrating food drastically decreases its bulk and weight, thus making it easily transported and stored for long durations.
Proper preparation is key when dehydrating food, which starts with washing it. Blanching certain foods such as fruits and vegetables prior to dehydrating is essential for preventing bacterial growth and protecting the original color, flavor, and texture.
The food is then cut into small pieces and dried in either a dehydrator or an oven.
The precise temperature requirement and duration of the process will depend on the food involved, usually ranging from 130-140°F and lasting between 4-24 hours.
It’s important to frequently monitor the food’s moisture level to ensure that it has been properly dehydrated. When the cooking is complete, the food should be dry and leathery to the touch.
Preserving dried food items requires either an airtight container or vacuum sealing for extended shelf-life.
Food preservation through dehydration is a great option for long-term storage as it does not require any special equipment and effectively maintains the nutrient, flavor, and texture of the food.
However, it is important to note that it may not kill bacteria or other microorganisms, so it is recommended to store the food in a cool and dry place, and to reheat or cook the food before consuming it.
Freezing
Keeping food fresh for an extended period is simple with freezing; a popular method of preservation that doesn’t require advanced equipment.
Food preservation using temperatures below its freezing point, usually around 0°F (-18°C), is the process of freezing food. Vegetables must be blanched or cooked before being frozen to stop enzymes from breaking down the food and maintain good quality.
Blanching is the process of heat treating the vegetables and then immersing them in cold water to stop the cooking process.
By taking this step, you can prevent changes in flavor and color that may take place during freezing. Boiling water typically blanches food for three minutes.
Fruits can be preserved by freezing them as-is, or adding sugars or antioxidants to extend shelf life and reduce color changes.
Once the fruits and vegetables have been cut and prepared, they should be spread out on a cookie sheet, frozen, and then placed in vacuum sealed packages to keep them preserved for long-term storage.
Packaging frozen food into vacuum sealed bags can significantly extend its shelf life, as it helps to avoid the formation of ice crystals which may otherwise reduce the longevity by three to five times.
This explains why vacuum sealed bags are the preferred option for storing frozen foods.
Freeze Drying
Lyophilization, commonly referred to as freeze drying, is a food preservation technique which involves freezing the food and then eliminating the moisture via a vacuum.
The process of preservation keeps microbes, enzymes, and oxidation in check, allowing food to stay fresher for longer.
Freeze drying is an effective preservation method for a variety of food items, for example fruits, vegetables, seafood, and complete meals.
Freeze-drying is a popular method of food preservation and is often used for astronaut meals, camping or emergency food supplies because it retains the flavor and nutritional value of the food.
Freeze drying involves a series of steps.
Food is typically flash-frozen at temperatures between -40°F and -60°F for the first step.
The second step involves transferring the frozen food to a vacuum chamber, where the atmospheric pressure is lowered and the ice starts sublimating from solid to gas state.
Using a heater can help accelerate the sublimation process for this procedure.
After the freeze-drying process is over, airtight packaging is used to protect the food from moisture and oxygen.
To safeguard the food from light, this packaging is typically done in Mylar bags, which can help delay spoilage.
The significant advantage of freeze-drying is that it can maintain the flavor and nutritional value of food.
Moreover, freeze-dried meals occupy minimal space and are lightweight, making them easy to store and carry around.
Despite its cost and energy consumption, freeze drying requires specialized equipment and can be a lengthy process. Additionally, it may not be suitable for food products with high moisture levels or food items that are heat-sensitive.
For most people or households, freeze drying may not be a practical way of preserving food, but it can be an effective option for those aiming to store food long-term.
See Harvest Right for more information.
Fermentation
Fermentation is a process of preserving food in which low-acid foods are transformed into highly acidic ingredients by means of salt, whey, or specific microorganisms.
Through the process of fermentation, food gains a distinct flavor and texture, as well as becoming easier to digest and more nutritious. This ancient preservation technique has been used for centuries.
The process of fermentation involves adding lactobacillus, a beneficial bacteria, to the food so it can consume starches and sugars and produce lactic acid as a result.
The acidity created by the lactic acid inhibits the growth of bacteria and mold, thus preserving the food.
Fermented foods like sauerkraut, kimchi, pickles, yogurt, kefir, and sourdough bread are popular.
These foods created by the process of fermentation are referred to as “live culture” due to their high amount of probiotics and beneficial bacteria.
Fermenting food at home is relatively easy. All you need to do is mix the food with salt and let it sit at room temperature for a few days.
Certain fermented foods, such as yogurt, may require certain temperatures and tools to make; however, many can be easily prepared with basic supplies such as mason jars and a piece of fabric.
Fermented foods are not just a great choice for extending shelf life, but they also provide numerous health benefits. The probiotic content of these products can help improve digestion, support the immune system, and even aid with weight loss.
Fermentation not only makes food items taste better, but also helps in preserving products that wouldn’t normally keep well over time like dairy items and prepared meals.
Incorporating a variety of nutritious, long-lasting foods into your diet is a fun and simple way to stay healthy.
Preserving in Salt and Sugar
Salt and sugar curing has long been a traditional way of preserving food.
This preserves food by disrupting the growth of microorganisms and pests through osmosis, often done by using salt and sugar either together or individually.
Salt curing is a food preservation technique that involves using salt, either by rubbing it in, packing it onto the food, soaking the food in brine, or injecting brine into the food.
Curing is a popular technique for treating meat like bacon, ham, and other pork items.
Salt curing helps to remove moisture from food, making it difficult for bacteria and other microorganisms to survive.
The sugar curing technique entails submerging foods in a sugary solution and is heavily utilized for meats like ham and bacon, as well as fruits and vegetables.
Sugar curing is a way of dehydrating food while simultaneously creating an environment unsuitable for bacteria or other microorganisms.
When using salt and sugar to preserve food, it is important to keep in mind that it may alter the flavor and texture of the food.
For those with an adventurous palate, this method is ideal. Adding salt and sugar to herbs, creating an infusion, is a way in which the flavors can be preserved.
It’s worth noting that, while preserving food in salt or sugar can increase its shelf life, it should be kept in a cool, dry place to avoid making the food overly salty or sweet.
In addition, it is important to rinse or soak the food in water before eating to remove any excess salt or sugar.
Immersion in Alcohol
Food preservation through alcohol immersion involves submerging the food in a strong alcoholic beverage such as vodka or brandy.
This method utilizes dehydration to prevent microbial and enzymatic spoilage by removing water from food.
Due to its high alcohol content, alcohol can be used to eradicate bacteria and other microorganisms that may be present on food.
This approach is best for small amounts of food, like herbs or fruits, since adding too much food to inadequate amounts of alcohol may not properly preserve it.
When marinating food, the liquor you choose should complement the flavors, as it may affect the taste of the final dish.
It should be noted that submerging food in alcohol is an effective way to preserve it, however, it is not advised for meats or any food high in protein since the alcohol content can cause the proteins to degrade, resulting in a mushy texture.
Furthermore, it is not advisable to consume large amounts of food that has been preserved this way as the alcohol content can be quite high.
When stored properly in a cool, dark place, food that is preserved in alcohol can have a shelf life of up to a year or more.
It’s essential to inspect the food regularly for indications of spoilage, like mold or an odd smell.
Vacuum Sealing
Vacuum sealing is an effective way of preserving food items by removing the air from the packaging.
The process of vacuum sealing involves removing air from the packaging and creating an airtight seal that keeps microorganisms and enzymes from growing, thereby preserving freshness.
The lack of oxygen helps to prevent oxidation, which is a major contributor to food spoilage.
Vacuum sealing is a process that can be used to preserve all sorts of foods, including fruits, vegetables, meats, and dairy products.
However, vacuum sealing does not fully dry the food nor can it eliminate any microorganisms.
In order to prevent spoilage, vacuum-sealed foods must be kept in either a fridge or freezer.
Vacuum sealing is an advantageous technique for preserving dehydrated foods, as it prolongs their expiration date. Vacuum sealed, dehydrated foods have a shelf life of up to 5 years or more.
Using a vacuum sealer in combination with other preservation techniques, like freezing and dehydrating, is an effective method of preserving food.
A disadvantage of vacuum sealing is the need for specialized equipment and bags. The cost of a vacuum sealer and bags can be prohibitive, making it an unsustainable investment for some.
It is possible to employ some DIY methods such as using Ziplock bags and inexpensive materials such as tubing and syringes to achieve vacuum sealing, though these are usually not as effective as store-bought products.
In summary, vacuum sealing is a useful technique for preserving food for extended periods of time, particularly dehydrated items. It is a dependable method for the elimination of oxygen, which creates the necessary seal to dimistish microbial activity and halt enzyme activity.
Still, specialized equipment and bags are needed for this, which can be pricey.
Oxygen Absorbers
Oxygen absorbers are packets that consist of iron powder, salt, and clay. These packets are made to enable oxygen to come in while blocking out exits.
Activating the iron powder with salt and clay causes it to absorb oxygen molecules.
Using oxygen absorbers is a great way to preserve food as they remove the oxygen necessary for microbial and enzymatic growth.
When it comes to maintaining the freshness of food for a long period, oxygen absorbers in combination with Mylar bags, which keep their seal for extended periods, can be of great help.
Foods that have been dehydrated or freeze-dried, packaged in Mylar bags with oxygen absorbers, can remain fresh for 15 years or more.
In comparison to other methods of food preservation such as vacuum sealing, which only increases shelf life for a few years, this offers a substantial advantage.
Using oxygen absorbers is simple and they can be bought through shops, or with many store-bought vacuum sealing machines.
It is important to note that oxygen absorbers alone are not enough to guarantee the freshness and safety of your food, as pests can still find ways to contaminate it if you don’t use proper storage containers.
Oxygen absorbers are an ideal choice for those interested in long-term food preservation.
Conclusion
Preserving food is a helpful skill that can come in handy in situations such as emergency preparedness, homesteading, and simply to have a sense of personal accomplishment.
One can select the proper food preservation technique for their circumstances by being aware of the causes of food degradation, including microorganisms, enzymes, oxygen, pests, and light.
Food preservation for long-term storage can be achieved through canning, dehydration, freezing, freeze drying, fermentation, preserving in salt and/or sugar, immersion in alcohol, vacuum sealing, and utilizing oxygen absorbers.
It’s important to pick an appropriate method considering the type of food, desired shelf life, and accessible resources and machinery. Every option has its own advantages and disadvantages.
Having the right information and methods, anyone can become an expert in long-term food preservation.