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How to Preserve Food
Home Food Storage:
Food preservation has been important throughout the history of mankind, and continues to be important in everyday life. Preservation of food helps to ensure that we can meet our daily food needs consistently. Food preservation is used everyday by nearly every person, but many just think of it as an everyday chore.
If you use a refrigerator or freezer than you already use food preservation methods. Some of the methods that will be mentioned are not used as frequently as they used to be in the past, but understanding the various techniques will give you more options in the future in the event that your current methods are not possible.
While this list will cover many different methods, this is by no means an all inclusive list and there are far more food preservation methods out there. Some are far too complicated to cover in this article, and others were not tried-and-true enough for me to be confident in including them.
Use Care & Caution:
There have been many wonderful technological innovations that have made food preservation, fast, easy, and more convenient, but it is very important that you not allow this to make you careless. Food safety must always be practiced! Avoid cross contamination by washing your hands frequently, sterilize any items that you can, and consume preserved foods in a timely manner so you do not risk getting sick.
Some methods discussed in here can give food a long shelf life, possibly even nearly infinite, but it is important that this not be tested unless absolutely necessary! I do not advocate leaving food sitting on shelves for years on end because with each passing day, you risk it spoiling and becoming potentially deadly!
Please note that this article is written for informational purposes only and any attempts to use the methods contained in this article is done at your own risk.
What Is Freezing:
Freezing is the process of preserving food by means of low temperatures. The low temperature makes it difficult for microorganisms to grow, it slows decay, and it slows down chemical reactions that render food less edible.
How Is It Done:
The food is placed into an environment that is so cold that it prohibits the growth of bacteria, mold and fungi. This is often accomplished by using a commercial freezer, refrigerator, or ice box. A more primitive method is placing food in a hole dug into snow. Caves are often used to keep wine chilled while the winery is letting it age.
A Small History:
This method of preservation has been used in cold climates for centuries. Many arctic indian tribes would store animal meat that they had hunted in holes they dug in the snow. This was a precursor to the Larders that were used before refrigeration technology was developed.
After larders, the domestic ice boxes arrived, and after the domestic ice boxes the home refrigerator took the markets by storm. Now, nearly every household in the industrialized world has a freezer or refrigerator in some kind of respect. This has lead refrigeration to being the most domestically popular method of food preservation.
What is Vacuum Sealing:
Vacuum sealing is becoming quite popular since the advent and proceeding decline in price of the home vacuum sealing machines. Vacuum sealing removes air from the environment that the food is stored in which slows down decay, oxidation and prevents microorganisms and fungi from growing.
This is a very popular method for increasing the shelf life of already dried foods such as rice and beans, and is fantastic when paired with other preservation methods like freezing. The removal of the air combined with these other methods of preservation renders the food a nearly unlimited life span. It is highly recommended, however, that you still use the food in a timely manner as punctures and other unforeseen circumstances can occur.
How is it done:
Vacuum sealing is ordinarily done with machines. One popular brand that is available at nearly all big box stores is called FoodSaver. The basic idea is that the food is placed into an approved bag then the bag is placed into the sealing machine which then sucks all of the air out and seals the bag in one process. The machines make this method surprisingly simple and convenient. Some drawbacks are the cost of the machine and the bags. The bags tend to be pricey and are a recurring cost.
The quality of the machines used to be a huge drawback but as technology has progressed the machines have become surprisingly dependable and the companies tend to be very good about supporting them and sending out the necessary parts in the event that something breaks. I can't speak for all companies but FoodSaver has been wonderful to me.
A Small History:
Because the technology is fairly new, there is little history with this method of food preservation. Removal of air and creating a vacuum is a foundation of canning and this is probably where vacuum sealing would get most of its history.
What Is Canning:
Canning is a means of preserving food by placing it into a glass jar and exposing the jar to heat to kill any microorganisms in the food. The exposure to heat is accomplished by submerging the jar in boiling water which kills the microorganisms and creates a vacuum environment that helps retard the growth of fungi and bacteria.
How Is It Done:
Acidic foods are placed into the sterilized glass jar, the sterilized flat lid is placed on the clean brim of the jar, and the ring is then screwed down. The jar is then placed in the proper pot of boiling water where it is processed. Once processed the jars are removed from the boiling water and left to cool at room temperature. Once cooled you must check that a good seal has been made on each jar by examining around the brim and by pressing the center "dimple" of the flat lid. It should not press down if a proper seal has been made.
Less Acidic, or non-acidic foods must be processed in a similar manner but inside of a pressure cooker. This will provide the correct amount of heat to kill bacteria and safely process the food.
Even the most experienced canners run into problems sometimes so be very careful. Check each jar for cracks and chips before placing food into them. Never place your jars directly onto the bottom of the pot, and make sure the jar brim is clean before placing the flat lid onto it. Always check your seals after cooling and always check your seals before you consume the food.
A Small History:
Canning has been used for the past 200 years roughly and, when done properly, yields excellent results. It was first began in France when the government awarded an inventor for the best method of preserving food for their army. Since then, canning has been very popular.
Canning is popular in farm areas where large amounts of food are produced and needs to be stored. Acidic foods can be canned with a quick boil, but less acidic foods, or meats need to be done in a pressure cooker to ensure that they are free of any bacteria. Canning is a great way to preserve foods but you must be fastidious when canning because not sealing the canister properly can lead to contaminated food that can be fatal.
What Is Drying:
Drying food is one of the oldest methods of food preservation. There are many ways to dry food including: in the sun light, in a dehydration machine, and by fire. Usually, they method you choose will depend mainly on the climate that you live in. If you live in a snowy and cold climate, then you may need to use the oven method or the dehydration machine. If you live in a hot and humid climate you can either use the oven, fire, or dehydration machine. If you live in a hot and dry climate then you can easily just sun dry your food without issue.
It is important to place your food where air can circulate all around it, like on a screen. Placing it onto something akin to a cookie sheet will only allow the air to circulate over it and may leave the part laying on the sheet moist. It is also imperative that you not place the food into too hot an environment as this can make the food hard on the outside and prevent the inside from dehydrating.
It is very important that you not leave food out in weather that is too humid as your food can be easily spoiled. You also want to make sure that the food is adequately covered to avoid insects, debris, and animals from contaminating it. Another great tip is to pasteurize your food after it is dehydrated. This is done by placing dehydrated food into the oven at about 115 - 120 degrees Fahrenheit for 15 minutes.
How is it done:
Drying can be done a number of ways such as putting the food in the sun (commonly used for making Grapes into Raisins), a dehydrating machine (commonly done for Beef Jerky), and open fire which is a more primitive method. Each method has its merits and all can be used to a stunningly effective extent, but my favorite is over a fire. The trick is to keep it far enough from the flame that it doesn't cook the meat but close enough that it can provide enough heat to pull the moisture out.
What is Pickling:
Pickling is another widely used method of preservation. It is commonly accomplished by submerging food in Vinegar or by submerging it in a brine solution (Salt and water). Pickling allows food to remain shelf stable by creating a very unfriendly environment to bacteria. A food submerged in brine can last years and still be safely eaten if done properly. Pickling is a very popular commercial method of preservation and is used in everything from pigs feet to pickles.
Pickled food has a very characteristic flavor to it due to the brining fluid and many different recipes exist on line for free that allow you to bring new and delicious flavors to your food. Pickling is often used in tandem with canning to yield high quality, shelf stable food that can remain for years to come.
How is it done:
Pickling is done simply by placing a food into a brine solution. The solution must have either a high salt, or high vinegar content in order to create the hostile environment that bacteria cannot live in. Many recipes are already available to you by doing a simple search online so you do not have to guess at what will work and taste good.
What is Curing:
Curing food is a means of preservation where the food is either placed in salt or smoked by fire. The salting of the food draws out moisture which prevents the growth of fungi and bacteria. Smoking the food encases it in nitrates and nitrites which prevent the growth of fungi and bacteria. Smoking also adds a distinct flavor to the food being treated. Curing food is an easy way to preserve food and to add flavor at the same time. As a side note, the concentration of the salt on the food should be upwards of roughly 20% or more to properly eliminate most bacterial growth.
How is it done:
The idea is very simple: life needs water, bacteria is life, bacteria needs water, and curing removes water. This creates an environment that bacteria cannot thrive in. Many people like to use various recipes for curing such as half salt half baking soda. No matter what your recipe, the goal is to draw out as much water as fast as possible to get the nicest, and safest result. Food can be re-hydrated by soaking it in warm to hot water, but may have an altered taste due to the salt and the change it has undergone.