This slide will give you detail information on preservatives.

1. By
Shaikh Saniya

2.  Introduction
 Types of food preservatives
 1.Natural
 2.Chemical
 3Artificial
 Common preservatives
 Common preservatives technique
 Role of food preservatives
 Side effects
 Awareness
 Reference

3.  A preservative is a substance or a chemical that is added to
products such as food, beverages, pharmaceutical drugs, paints,
biological samples, cosmetics, wood, and many other products to
prevent decomposition by microbial growth or by undesirable
chemical changes. In general, preservation is implemented in two
modes, chemical and physical.
 Chemical preservation entails adding chemical compounds to the
product. Physical preservation entails processes such as
refrigeration or drying. Preservative food additives reduce the
risk of food borne infections, decrease microbial spoilage, and
preserve fresh attributes and nutritional quality.
 Some physical techniques for food preservation include
dehydration, UV-C radiation, freeze-drying, and refrigeration.
Chemical preservation and physical preservation techniques are
sometimes combined

4.  Food preservation prevents the growth of
microorganisms, or other microorganisms, as
well as slowing the oxidation of fats that
cause rancidity. Food preservation may also
include processes that inhibit visual
deterioration, such as the enzymatic
browning reaction in apples after they are cut
during food preparation.

5. 1. Natural Food Preservatives
2. Chemical Food Preservative
3. Artificial Preservatives

6.  Natural food preservatives like salt, sugar, alcohol,
vinegar etc. These are the traditional preservatives in
food that are also used at home while making pickles,
jams and juices etc. Also the freezing, boiling,
smoking, salting are considered to be the natural
ways of preserving food.
 Coffee powder and soup are dehydrated and freeze-
dried for preservation. The citrus food preservatives
like citrus acid and ascorbic acid work on enzymes
and disrupt their metabolism leading to the
preservation.
 Sugar and salt are the earliest natural food
preservatives that very efficiently drops the growth of
bacteria in food.
 To preserve meat and fish, salt is still used as a
natural food preservative.

8.  Salt is an essential one of the natural food
preservative additives. It is mostly used for
preserving meats and other non-vegetarian
foods. Salt is instrumental providing protection
from yeasts, molds and bacteria by dehydrating
the microbes with a process called osmosis,
curbing the growth of food spoiling bacteria and
therefore enhancing the life of food being
preserved.
 Or in layman terms, salt binds the water by
entering the tiny food tissues, drawing out the
moisture completely. Thus, reducing the chances
of food getting spoiled for, longer than normal
spans.

9.  sugar is also an everyday food ingredient and in
unfailingly found in every kitchen. Other than being
used as a sweetener, sugar is also among commonly
used natural food preservatives. Sugar also uses the
same concept of osmosis just like salt, where its
soaks up all the moisture from the food being
preserved and obstructing the growth of any food
spoiling bacteria.
 Preserved foods are either stored in a sugar syrup or
in the crystallized form. Sugar is usually used to
preserve fruits like apple, plum, peach, pear, etc. The
way these fruits are preserved, the sugar preservative
content works as a sweeteners and enhanced the
taste of these fruits overtime

10.  Rosemary leaf extract is also widely used as
natural preservative. Traditionally the extract
has been used primarily for its nice aroma
and flavor. But due its food preserving
capabilities, rosemary extract is now also
used for preserving food.
 Its main quality is that it serves as an
antioxidant, thus preventing the oxidations of
the ingredients that are prone to any form of
spoiling. It effectively retains the color and
the flavor in the food.

11.  Onion as a natural food preservative is quite a
popular preservatives additive. It contains
antioxidant and antimicrobial properties,
which is the main reason for onion being one
of the best natural food preservative
alternatives to artificial food preservatives.
 Yellow variety of onions is said to be the most
effective food preservative variety. The
flavonoids in the yellow onions have
beneficial properties for health in general as
well as for food preserving needs.

12.  Chemical food preservatives are also being used
for quite some time now. They seem to be the
best and the most effective for a longer shelf life
and are generally fool proof for the preservation
purpose. Examples of chemical food
preservatives are:
1. Benzoates (such as sodium benzoate, benzoic
acid)
2. Nitrites (such as sodium nitrite)
3. Sulphites (such as Sulphur dioxide)
4. Sorbates (such as sodium sorbate, potassium
sorbate

13. Antioxidants are also the chemical food
preservatives that act as free radical
scavengers. In this category of
preservatives in food comes the vitamin
C, BHA (butylated hydroxyanisole),
bacterial growth inhibitors like sodium
nitrite, sulfur dioxide and benzoic acid.
Then there is ethanol that is a one of the
chemical preservatives in food, wine and
food stored in brandy.
Unlike natural food preservatives some
of the chemical food preservatives are
harmful.
Sulfur dioxide and nitrites are the
examples. Sulfur dioxide causes irritation
in bronchial tubes and nitrites are
carcinogenic.

14.  Artificial preservatives are the chemical
substances that stops of delayed the growth
of bacteria, spoilage and its discoloration.
These artificial preservatives can be added to
the food or sprayed on the food.
Types of Artificial Preservatives Food
1. Antimicrobial agents
2. Antioxidants
3. Chelating agent

15.  In antimicrobial comes the Benzoates, Sodium
benzoate, Sorbates and Nitrites.
Antioxidants include the Sulfites, Vitamin E,
Vitamin C and Butylated hydroxytoluene (BHT)
Chelating agent has the Disodium
ethylenediaminetetraacetic acid (EDTA),
Polyphosphates and Citric acid.
Harmful Food Preservatives
 Although preservatives food additives are used to
keep the food fresh and to stop the bacterial
growth. But still there are certain preservatives in
food that are harmful if taken in more than the
prescribed limits.


16. Butylates
 This chemical food preservative is expected to
cause high blood pressure and cholesterol level.
This can affect the kidney and live function. It is
found in butter, vegetable oils and margarine.
BHA (butylated hydroxyanisole)
 BHA is expected to cause the live diseases and
cancer. This food preservative is used to preserve
the fresh pork and pork sausages, potato chips,
instant teas, cake mixes and many more.

18.  Refrigeration
 Freezing
 Drying, curing and conserving
 Vacuum and oxygen free modified atmosphere packaging
 Carbon dioxide enriched and/or modified atmosphere packaging
 Addition of weak acids such as sodium lactate
 Lactic fermentation
 Sugar preservation
 Ethanol preservation
 Emulsification
 Addition of preservatives such as nitrite or sulphite ions
 Pasteurization
 Food irradiation
 Application of high hydrostatic pressure
 Pulsed electric field processing

19.  Food preservatives play a vital role in
preventing deterioration of food, protecting
against spoilage from mold, yeast, life-
threatening botulism and other organisms
that can cause food poisoning. By extension,
preservatives reduce food cost, improve
convenience, lengthen shelf life and reduce
food waste.

20. Oversight
 The FDA has jurisdiction over all
preservatives, with the Food Safety and
Inspection Service sharing responsibility for
the safety of food additives used in meat,
poultry and egg products. The FDA mandates
that preservatives not be used in such a way
as to conceal damage or inferiority, make the
food appear better than it is or adversely
affect the nutritive value of the food. Food
additives approved for use as preservatives
are listed in the U.S. Code of Federal
Regulations.

21. Safety
 According to the regulatory authorities,
preservatives are generally recognized as
safe, or GRAS, in the quantities in which they
are allowed in individual food products. “Safe”
for food additives is defined to mean “a
reasonable certainty in the minds of
competent scientists that the substance is not
harmful under the intended conditions of
use.” Still, there are some preservatives of
concern.

23.  Harmful food preservatives have been
accused of many health hazards ranging from
mild headaches to most serious diseases like
cancer. However, not all food preservatives
are harmful, especially if they have been
manufactured in controlled situations and
used in food items in amounts permissible by
food laws

24.  Public awareness of food preservatives is uneven.
Americans have a perception that food-borne
illnesses happen more often in other countries. This
may be true, but the occurrence of illnesses,
hospitalizations, and deaths are still high. It is
estimated by the Center for Disease Control (CDC)
that each year there are 76 million illnesses, 325,000
hospitalizations, and 5,000 deaths linked to food-
borne illness.

 The increasing demand for ready-to-eat fresh food
products has led to challenges for food distributors
regarding the safety and quality of their foods.
Artificial preservatives meet some of these challenges
by preserving freshness for longer periods of time,
but these preservatives can cause negative side-
effects as well.

25. THANKYOU