food preservation - pickles

Canning Pickles as a Method of Food Preservation

First done by Frenchman Nicolas Appert in 1809, canning pickles as a method of food preservation essentially remains the same. This method generally involves heating the container until it reaches the required temperature to kill bacteria responsible for food spoilage- a process also called heat processing. What results from this a vacuum container which can keep the pickles for as much as a whole year.

The process is simple enough- which undoubtedly adds to its appeal. In order to do it, all you need are (1) glass canning jars and 2-piece metal canning lids, (2) a large, non-reactive stainless steel pot with a secure lid, (3) a jar rack, (4) Tongs, (5) Rags, and (6) a timer. When all the materials are present, make sure to wash the jars with water and soap, thoroughly cleaning the inside as well as the outside of the containers. Afterwards, place them on the rack which should be inside the metal pot.

Read the rest of this entry »

Food preservation methods

Taken from http://healthyeatingclub.com/info/articles/food-proc/food-pres.htm

Method	Advantages	Disadvantages
Drying (e.g. freeze-drying, spray-drying, sun-drying)	Produces concentrated form of food. Inhibits microbial growth & autolytic enzymes. Retains most nutrients.	Can cause loss of some nutrients, particularly thiamin & vitamin C. Sulphur dioxide is sometimes added to dried fruits to retain vitamin C, but some individuals are sensitive to this substance.
Smoking	Preserve partly by drying, partly by incorporation of substances from smoke.	Eating a lot of smoked foods has been linked with some cancers in some parts of the world.
Refrigeration	Slows microbial multiplication. Slows autolysis by enzymes	Slow loss of some nutrients with time
Freezing	Prevents microbial growth by low temperature & unavailability of water. Generally good retention of nutrients.	Blanching of vegetables prior to freezing causes loss of some B-Group vitamins and vitamin C. Unintended thawing can reduce product quality.
Adding salt or sugar	Makes water unavailable for microbial growth. Process does not destroy nutrients.	Increases salt and sugar content of food.
High heat processing (e.g. pasteurization)	Inactivates autolytic enzymes Destroys microorganisms.	Loss of heat-sensitive nutrients.
Canning (involves high heat processing)	Destroys microorganisms & autolytic enzymes.	Water-soluble nutrients can be lost into liquid in can.
Chemical preservatives	Prevent microbial growth No loss of nutrient.	Some people are sensitive to some chemical preservatives.
Ionizing radiation	Sterilizes foods (such as spices) whose flavour would change with heating. Inhibits sprouting potatoes Extends shelf life of strawberries and mushrooms	Longer shelf life of fresh foods can lead to greater nutrient losses than if eaten sooner after harvesting.