Food Preservation

2. Food preservation is one way of
keeping food for future use. It is the
process of treating and handling food
to stop or slow down spoilage, and to
prevent food-borne illness while
maintaining nutritional value, texture or
the consistency of food, and flavor.
Learning to preserve food can benefit
you and your family. This can generate
income or simply serve as a constant
source of food.

3. There are many kinds of food that can be preserved, the
most common of which are fruits. Fish, meat, and eggs can also
be preserved.
Preservation involves preventing the growth of bacteria,
fungi, and other microorganisms, as well as inhibiting the
oxidation of fats, which causes rancidity.
Common preservation methods include drying, spray drying,
freeze drying, freezing, vacuum-packing, canning, and adding
preservatives or inert gases such as carbon dioxide.
Other methods that not only preserve food but also add flavor
include pickling, salting, smoking, preserving in syrup or alcohol,
sugar crystallization, and curing.

4. One of the oldest methods of
food preservation, drying reduces water
activity to delay or prevent bacterial
growth. Most types of fish and meat
can be dried (like tuyo or daing).
Drying is especially valuable in the case
of pork, since it is difficult to keep
without preservation. Fruits like bananas,
mangoes, papaya, and coconut can also
be dried. Raisins are a form of dried
grapes. Drying is also the normal
means of preservation for cereal grains
such as wheat, corn, oats, and rice.

5. Meat, fish, and some other foods
may be both preserved and flavored
through the use of smoke, typically in
a smoke-house. Heat dries the food
without cooking it, and along with the
aromatic hydrocarbons from the smoke,
food is preserved. Smoked fish or
tinapa is especially delicious when
eaten with fried rice, tomatoes, and
bagoong.

6. Freezing is also one of
the most commonly used
commercially and domestically,
for preserving a wide range
of food kinds like meat
Frozen foods include ham,
bacon, hotdogs, ground beef,
and chicken. processes,

7. Vacuum-packing stores food
in a vacuum environment,
usually in an air-tight bag or
bottle. Home vacuum-packing is
available in bags, canisters,
jars, and bottles. The vacuum
environment strips bacteria of
oxygen needed for survival,
hence preventing the food from
spoiling. Vacuum-packing is
commonly used for storing nuts.

8. Salting or curing draws moisture
from the meat through osmosis. Meat
is cured with salt or sugar, or a
combination of the two. Nitrates and
nitrites are also often used to cure
meat. This is the process followed by
the famous etag in the Cordilleras.
Etag is sun-dried and salted meat,
usually pork, which can be eaten raw.

9. Sugar is used to
preserve fruits, either in
syrup with fruit such as
apples, coconut, lychees,
garbanzos, langka, papaya,
and pineapple; or in
crystallized form where the
preserved material is cooked
in sugar to the point of
crystallization. The product is
then stored dry. This method
is also used for the skins
of citrus fruit, and for
ginger.

10. Pickling places or cooks food in a
substance that kills bacteria and other
microorganisms. This material must also
be fit for human consumption. Typical
pickling agents include brine, which is
high in salt: vinegar; ethanol; and
vegetable oil, especially olive oil. Most
pickling processes also involve heating
or boiling so that the food becomes
saturated with the pickling agent.
Frequently-pickled items include vegetables
and fruits like cabbage, papaya, pepper,
pipino, santol, and mangoes, and some
animal products like corned beef and
eggs.

11. Canning involves cooking fruits or
vegetables, sealing them in sterile cans
or jars, and boiling the containers to
kill or weaken any remaining bacteria.
Foods have different degrees of
natural protection against spoilage, and
may require that the final step occur
in a pressure cooker.
Lack of quality-control in canning
may allow the entrance of water or
microorganisms. Most such failures are
immediately detected, as decomposition
within the can produces gas, causing
the can to swell or burst.

12. Food may be preserved
by cooking in a material
that solidifies to form a
gel. Such materials include
gelatine, agar, and
arrowroot flour. Some
foods naturally form a
protein gel when cooked,
such as pig's feet or
cow's feet.

13. Successful food preservation depends on the equipment used. These
include the following:
1. Good jars with tightly-sealed covers. The size of the jar is
determined by the amount of food to be preserved. Jars
should be washed in soapy water, then scalded.
2. A deep broiler with a well-fitted cover and rack for
processing; big kettles or tin petroleum cans with covers;
homemade wire racks.
3. Other equipment like measuring cups, short- and long-handled
spoons, knives, colanders, trays, basins, bowls, tongs, and jelly
bags.