Food Marketing & Technology - India June 2019 | Page 36

Processing
longer under controlled conditions.
Heating involved in the canning
process destroys microorganisms
and spore-forming bacteria. The air is
driven out of the can and as it cools
the can is vacuum sealed. This vacuum
seal prevents air from getting back
into the product and protects it from
contamination.
Purpose of Canning
CANNING –
ALL YOU NEED TO KNOW!
BY: GAGAN DIP AND DAMINI SAHU *
I
n the current situation, food
preservation has become a very
important aspect of our lives. As
we see, food production and supply do
not always go well with the demand or
meets of the people. Several foods e.g.
fruits and vegetables are available in
a specific season and are not available
throughout the year. At some places,
there is a surplus production of a
particular food product, while at the
same time at different places there is
an inadequate supply. Certain foods
are highly perishable, they quickly
turn bad or deteriorate because of high
microbial growth; and semi-perishable
like juicy fruits, vegetables, mangoes,
tomato, papaya and many more, which
very quickly gets spoilt. It is therefore
very important in order to maintain
seasonal foods intact for later use. This
can be done by improving the shelf-
life of food by maintaining proper
storage with effective preservation
techniques. Food preservation helps in
addressing all of the above mentioned
problems such as: increasing the shelf-
life of foods; increasing the availability
of seasonal foods throughout the
year; reducing wastage of food by
preventing decay or spoilage of food;
etc.
In order to effectively combat with
such scenarios, modern age scientists
are busy in developing techniques
to maintain seasonal foods intact for
later use. They believe that effective
preservation ensures the availability
of food at all times and its supply is
maintained. Among various other
techniques of preservation, canning is
one of the widely used options for the
preservation of food. Some examples
of foods which can be packed using can
packaging include: juices; sweets; fresh
fruits & vegetables; fish; meat; ready to
eat foods; soups; pet foods; etc.
What is Canning?
Canning is a technique for protection
and preservation of food in which the
food is heated and hermetically sealed
in containers such as: glass bottles;
metal cans; thermostable plastic; or
multilayer flexible. The shelf life of
canned foods is between six months
to 5 years and it can be even extended
Food Marketing & Technology
36
June 2019
The presence of high moisture in
various foods like fresh fruits
& vegetables makes them more
susceptible
to
spoilage.
The
microorganisms present on fresh
food multiply quickly and accelerate
the spoilage process. Proper canning
procedures help to minimize the effect
of microorganisms and make the food
safe for consumption for a longer
period of time.
The process used for canning food is
determined primarily by the acidity
of the food or mixture of foods being
canned. Based on their pH, foods are
categorised into the following classes:
Low acid Foods: The foods with a pH
range of 5.0 to 6.8 fall in this category.
The examples include: vegetables;
meats; poultry; seafood; dairy, etc.
Acid Foods: The foods with a pH
range of 4.5 to 3.7 fall in this category.
The examples include: pear; oranges;
apricots; tomatoes; and other citrus
foods.
High acid Foods: The foods with a
pH range of 3.7 down to 2.3 fall in this
category. The examples include: highly
acidic foods like pickled products and
fermented foods.
Methods of Canning
Boiling Water Bath Method: The
boiling water bath method can be
utilised for high-acid foods such as:
jams; marmalades; pickles; fruits;
tomatoes; fermented foods; foods
with vinegar; etc. The safe processing