Canning When you can food you use vinegar as your main preservative. Vinegar is very acidic and it is able to pickle items. This causes a bitter taste but also makes the food last longer. It is a solvent because there is more vinegar than water. A great example of this is pickles
Canning continued You put the can under high heat to make a air tight seal ( seal happens when it cools ) Air carries bacteria and when you can something you keep it at standard temp Any air can put bacteria into food which loves to grown in a can and can make you sick
Freezing You have a freezer The faster you put food into the freezer and the colder your freezer the quicker it will freeze. You want your food to freeze quickly because crystals that are small will form through out the entire meat this makes a equal thawing and less freezer burn. Taste will still be of high quality.
Liquid nitrogen Freezes food the quickest and is the best form of freezing food. It has the smallest ice crystals that form
Drying It is the oldest form It is also the most natural You need a dry climate to prevent moisture to go in with the food Moisture lets bacteria grow which makes you sick You can put it into your oven at 170 F or you can hang it out on a dry hot day
Drying continued Chemical process Moisture evaporates and leaves the fruit Sugar then condenses and when cools forms crystals. Food tastes sweeter because of the sugar concentration is now much higher. Water left changing the solution. Same amount of sugar but less water = more sweet
Importance When back packing food needs to be persevered because you are in all different climate of hot and cold Food being persevered can help you in a emergency and you will be able to eat and not worry about getting sick if you preserve food correctly. Eat all food with in 2 years of preserving it.