Meat, fish, fruits, and vegetables are highly perishable because they spoil easily. Once food is spoiled, it is no longer fit for consumption since it may cause loose bowel movement or LBM or may trigger other stomach reactions. Foods spoil because of molds and bacteria; they eat the food and they live in it.
In preserving food, molds and bacteria are prevented which cause the spoiling of food. And there are 5 ways to do this.
By keeping food at low temperature
Food placed in the refrigerator doesn't spoil for some time. That's why people who have refrigerators could buy a whole week supply of food. Meat, fish, vegetables, and fruits can be kept in the freezer for a long period of time without spoiling them. In the market you will notice some fish are stored inside the containers with ice in it to keep them fresh.
- Refrigeration and freezing are probably the most popular forms of food preservation today. In refrigeration, the bacterial action on the food is slowed down; it takes a week or two to spoil. In freezing, bacterial action on the food is stopped. Bacteria are completely inactive if frozen.
Almost all foods - meat, vegetables, fruits beverages and other foods can be preserved in refrigerator and freezer. Taste and texture of foods has no effect in refrigeration while in freezing, it has minimal effects on vegetables and fuits, and no effect on the taste of meat. Due to the minimal effects of refrigeration in foods, it has been accounted as popular form of preservation.
- Freeze-drying is a special form of drying. All moisture are removed and food taste won't be affected than normal dehydration.
In freeze-drying, food is frozen and placed in a strong vacuum. This is used when making instant coffee. This also works well on fruits like apple.
Drying preserves some foods. Dried fish and meat are preserved foods. Legumes are preserved by drying, too. Mongoes, garbanzos, beans, are examples of dried seeds. They can be kept for a long time. Raisins are dried grapes.
- Dehydration. To preserve some foods you have to dehydrate them. Dried fruits, potatoes in a box, dried vegetables, powdered milk, pasta, powdered soups, powdered sauces, and powdered meat you see in the grocery store are dehydrated products.
When foods are dried, bacteria will become inactive. So, foods in air-tight containers will last for a long time.
If you like to personally dehydrate some foods, you might want to purchase a food dehydrator to speed up the process - NESCO FD-75A, Snackmaster Pro Food Dehydrator, Gray
By adding preservatives.
Substances that are used for preserving food are called preservatives. Sugar, salt, spices, saltpeter, and vinegar are examples of preservatives. Smoke also preserves some foods. Ham and bacon are cured by smoking. Candied fruits are preserved by sugar.
- Salting, especially of meat, is an ancient preservation technique. The meat covered by salt does not spoil because bacteria cannot thrive in salty environment. Moisture in food is also drawn out by salt. When meat is salted in cold weather, it will last for years.
- Pickling. In the past, this was widely used to preserve meat, fruits and vegetables. Today, it is used to make pickles such as pickled cucumbers. Preservative qualities of vinegar and salt are combined to produce pickles. Salt and vinegar inhibits the growth of bacteria.
How to make pickled cucumbers? Soak cucumbers in 10% saltwater brine for several days. Then, rinsed and stored in vinegar to preserve them. It's that simple!
If you like to preserve food the traditional way, this book might be useful to you - Preserving Food without Freezing or Canning: Traditional Techniques Using Salt, Oil, Sugar, Alcohol, Vinegar, Drying, Cold Storage, and Lactic Fermentation
By excluding air
Foods kept where air cannot reach them is preserving by excluding air. Canned foods kept air out of the food. Canning is one of the most common ways of preserving food. Many foods can be canned. Sometimes it’s cheaper to buy canned foods than to can them at home. Preserving food at home is expensive if you need to buy the food to be preserved. The materials and equipment for preserving, like wide-mouthed glass jars, rubber, and pressure cooker, are costly. However, when there is good harvest, canning should be done so the food would not be wasted. Canned products should be kept in a cool, dry place. The jars of fruits, vegetables, and other preserves should be labeled properly. Shelves should be kept clean and arranged well so cans and jars could be seen easily.
- Canning. This has been around for many years since 1825. People can store foods in can for a very long time. The food in the can must be boiled to kill the bacteria and the can must be sealed - can be either before or while the food is boiling. The food in the can does not spoil because it is completely sterile. Once you open the can, you have to refrigerate its contents because bacteria will begin destroying the food.
Generally, cans are considered as being metal, but any sealable container - glass jar, plastic pouch or foil - can serve as a can. For example: milk in a box on the shelf is considered as "canned milk." Canned milk is made sterile by using ultra high temperature pasteurization, so even at room temperature it does not spoil.
Refrigeration and freezing are preferred to canning. Why? Because in canning you have to boil the food which can alter its taste and texture, and its nutritional content.
Using heat to kill bacteria is a good way to preserve food. This is called sterilization. Canned foods and preserved foods in jars have been sterilized.
Beth Arch (author) from Pearl of the Orient Seas on October 24, 2012:
Brandimae, thanks you've found this hub helpful.
Brandi Gregory from Jacksonville, Florida on October 01, 2012:
What a helpful list! I'll be using these. :)
Medifast Recipes on March 27, 2011:
Thanks for the dehydrating video, quite a tip indeed, I used to only know the keeping food at low temperature tip.
C.K on December 08, 2010:
THIS IS COOL in the other subject its so so so so so so so so so boring BUT IN THIS PAGE ITS SO SO SO SO SO SO SO SO SO SO SO SO SO SO CCCCOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLLL YEAH ROCKS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Renee Brown on October 15, 2010:
Thank you for the information and the pictuers that help me to fulfill my assignment
Beth Arch (author) from Pearl of the Orient Seas on January 21, 2010:
Thank you for visiting, Teresa. Godbless.
Maria Teresa Rodriguez - Laurente from San Antonio, Texas, U.S.A. on January 21, 2010:
Thank you for this very useful information. When I have some time left, I will try one of these. More power.
Beth Arch (author) from Pearl of the Orient Seas on November 06, 2009:
@ UMESH. Thanks for visiting my hub.
UMESH on November 06, 2009:
VERY VERY THANKS FOR PROVIDING THIS MUCH OF VALUABLE INFORMATION REGARDING ON THE FOOD PRESERVATION
Beth Arch (author) from Pearl of the Orient Seas on October 17, 2009:
Hi, Chin. Thanks for dropping by. I'm happy to know that you're also a Filipino like me.
Beth Arch (author) from Pearl of the Orient Seas on October 17, 2009:
Ambition & Waren,
Thanks for reading. I'm glad that you found this informative.
Chin chin from Philippines on October 17, 2009:
Hi Beth. I am a food technologist by profession though I did not practice it much because of having to stay at home to take care of our family. This hub is really informative for those who wants basics in food preservation. By the way, am also a Filipino. God bless.
Waren E from HAS LEFT THE BUILDING............ on October 13, 2009:
This was very informative I learned something new today!
Ambition398 on October 12, 2009:
Great suggestions! Some I had no idea on how do.