Food Preservation Methods
Millions of fruits and vegetables are
produced each year and they are lost due to poor processing and preservation.
Fresh fruits are abundant during the season and are not available during off
season. Due to this the food has to be stored until the next season. Fish and
meat too have to be pre-served as all that is killed or caught cannot be eaten at
one time. Bacteria, fungi and yeasts tend to decay the food and render it unfit
to eat. Hence all fresh foods have to be preserved if it is to be used after a
period of time.
Besides when food spoils, they undergo
physical and chemical changes that results in the food becoming inedi-ble or
hazardous to eat. The chief causes of food spoilage are;
·
The growth of microorganisms like
bac-teria, yeast and moulds.
·
The action of enzymes that
normally occur in the food.
Other causes of spoilage are non
enzy-matic reactions in food such as oxida-tion and mechanical damage such as
bruising and damage from rodents and insects.
In order to prevent food spoilage and ensure
food security and availabil-ity, various food preservation techniques have been
used over the several years. The earliest steps in food preservation are drying of grains and nuts. Later salting, smoking and drying were applied to
pre-serve the food.
Food preservation is known as “the sci-ence which deals with the
process of pre-vention of decay or spoilage of food thus allowing it to be
stored in a fit condition for future use”.
Preservation also can be defined as “the state in which any food may be retained over a period of
time without being contaminated by pathogenic organ-isms or chemicals, without
losing opti-mum qualities of colour, texture, flavour and nutritive value”.
Food production and supply does not always
tally with the demand or needs of the people. In some places, there is surplus production of food product,
whereas in some other place there is inadequate sup-ply. It is therefore
important to improve and expand facilities for storage and pres-ervation of food to ensure its
availability and acceptability at all times.
·
Increase in shelf life of foods.
·
Availability of seasonal foods
through-out the year.
·
Stability in prices of food as
there will not be a deficit in supply.
·
Good quality
·
Edibility – texture and flavour
·
Retention of nutritive value
·
Retention of original colour of
food.
For the process of preservation, a
preservative (e.g. salt, sugar, vinegar) is needed.
·
By keeping out microorganisms and preventing contamination from
pathogens. It involves apply-ing the strictest rules to minimize the risk of
infection (asepsis).
·
Removal of microorganism through usage of membrane which retains
microorganisms (filtration).
·
By hindering the growth and activity of microorganisms (refrig-eration, dehydration, addition of chemical
preservatives).
·
By killing microorganisms (boiling, irradiation).
·
By destruction or inactivation of enzymes (blanching).
·
By prevention or delay of chemical reactions (anti oxidants).
Related Topics
Privacy Policy, Terms and Conditions, DMCA Policy and Compliant
Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.