Preservation by Food Additives

8/2/2019 Preservation by Food Additives

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PRESERVATION BY FOOD

ADDITIVES

Submit to: - Sir Dr. Abdul Hassan Shar

By:- Najeeb-Ur-Rehman KhosoMS Part-I, 1st Semester

Department of Microbiology

Shah Abdul Latif University

Khairpur, Sindh



Index

Introduction

Function of food additives

Food Preservation

Preservation processes

Artificial Food Additivies

Sequesterant(preservatives)

Categories of food additives

References



Food Additives……….

Food additives are substances added to

food to preserve flavor or enhance its taste andappearance.

Some additives have been used for centuries;for example, preserving food by pickling (withvinegar), salting, as with bacon, preserving

sweets or using sulfur dioxide as in some wines. With the advent of processed foods in the

second half of the 20th century, many moreadditives have been introduced, of both naturaland artificial origin.



These additives generally provide some types of

benefits to the food producer, processor or

consumer.

For the consumer, additives can improve organoleptic

qualities of foods, improve the nutritive value, or ease

the preparation of ingredients and meals.

Typical additive benefits to the food producer or

processor include improving product quality, safety

and variety.



Additive may found in varying quantities in foods,

perform different functions in foods and ingredients,and function synergistically with other additives.

Additives that maintain product quality may alsoensure food product safety for the consumer. For,example, acids that may be added to prevent thegrowth of microorganisms that cause spoilage may

also prevent the growth of microorganisms that cancause foodborne illness.



FUNCTIONS OF ADDITIVES

Their functions can usually be classified as one of

the following:

To maintaining or improve nutritional quality

To maintain or improve product safety or quality

To aid in processing or preparations

To enhance sensory characteristics



FOOD PRESERVATION

Food preservation is the process of treating andhandling food to stop or slow down spoilage (loss ofquality, edibility or nutritional value) and thus allow forlonger storage

Preservation usually involves preventing the growth ofbacteria, yeasts, fungi, and other micro-organisms

(although some methods work by introducing benignbacteria, or fungi to the food), as well as retarding the

oxidation of fats which cause rancidity.



Many processes designed to preserve food willinvolve a number of food preservation methods.Preserving fruit, by turning it into jam, for example,

involves boiling (to reduce the fruit’s moisture contentand to kill bacteria, yeasts, etc.), sugaring (to preventtheir re-growth) and sealing within an airtight jar (toprevent recontamination).

Maintaining or creating nutritional value, texture andflavor is an important aspect of food preservation,

although, historically, some methods drasticallyaltered the character of the food being preserved. Inmany cases these changes have now come to beseen as desirable qualities – cheese, yoghurt and

pickled onions being common examples.



ARTIFICIAL FOOD ADDITIVIES

Preservative food additives can be antimicrobial;

which inhibit the growth of bacteria or fungi,

including mold, or antioxidant ; such as oxygen

absorbers, which inhibit the oxidation of foodconstituents.

Common antimicrobial preservatives include calcium

propionate, sodium nitrate, sodium nitrite, sulfites

(sulfur dioxide, sodium bisulfite, potassium hydrogen

sulfite, etc.) and disodium EDTA.



Antioxidants include BHA and BHT. Other preservatives

include formaldehyde (usually in solution), glutaraldehyde

(kills insects), ethanol and methylchloroisothiazolinone.

Whether the additive comes from a natural source or is

man-made, the question of safety is central to the decision

as to whether or not an additive should be permitted in

food.

A special class of additives that reduce oxidation is known

as the sequestrants. Sequestrants are compounds that

"capture" metallic ions, such as those of copper, iron, and

nickel, and remove them from contact with foods.



SEQUESTERANT(PRESERVATIVES)

Sequesterants are chelating agents. They areorganic compounds that react with metallic ions tobind in a relatively inactive structures.

Sequesterants prevent discoloration, flavor lossand odor loss.

Common Sequesterants include EDTA, citric acidits salts, and phosphoric acid and its salt.



Additives that maintain product quality may alsoensure food product safety for the consumer.

Additives that affect nutritional quality are primarilyvitamins and minerals. In some foods, these may beadded to enrich the food or replace nutrients that may

have been lost during processing.

In other foods, vitamins and minerals may be addedfor fortification in order to supplement nutrients thatmay often be lacking in human diets.



Additives that are used as processing or preparation

aids, usually affect the texture of ingredients andfinished foods.

Some of these are classified as emulsifiers,stabilizers, thickeners, leavening agents, humectantsand anti-caking agents.

Chemical in this group of food additives are alsoused to adjust the homogeneity, stability and volumeof foods.

Flavoring chemicals may be used to magnify theoriginal taste or aroma of food ingredients or to

restore flavors lost during processing.



Categories of food additives

Food additives can be divided into several groups,although there is some overlap between them.

AcidsFood acids are added to make flavors "sharper", and

also act as preservatives and antioxidants. Common

food acids include vinegar, citric acid, tartaric acid,malic acid, fumaric acid, and lactic acid.





Bulking agents

Bulking agents such as starch are additives that increase the

bulk of a food without affecting its taste.

Food coloring

Colorings are added to food to replace colors lost duringpreparation, or to make food look more attractive.

Color retention agents

In contrast to colorings, color retention agents are used to

preserve a food's existing color.

http://en.wikipedia.org/wiki/Food_coloring



Emulsifiers

Emulsifiers allow water and oils to remain mixed

together in an emulsion, as in mayonnaise, ice cream, andhomogenized milk.

Flavors

Flavors are additives that give food a particular taste orsmell, and may be derived from natural ingredients or

created artificially.

Flavor enhancers

Flavor enhancers enhance a food's existing flavors. Theymay be extracted from natural sources (through

distillation, solvent extraction, maceration, among other

methods) or created artificially.



Flour treatment agents

Flour treatment agents are added to flour toimprove its color or its use in baking.

Glazing agents

Glazing agents provide a shiny appearance orprotective coating to foods.

Humectants Humectants prevent foods from drying out.



Tracer gas

Tracer gas allow for package integrity testing toprevent foods from being exposed to atmosphere,

thus guaranteeing shelf life.

Preservatives

Preservatives prevent or inhibit spoilage of food dueto fungi, bacteria and other microorganisms.

Stabilizers

Stabilizers, thickeners and gelling agents, like agaror pectin (used in jam for example) give foods afirmer texture. While they are not true emulsifiers,

they help to stabilize emulsions.



Sweeteners

Sweeteners are added to foods for flavoring.Sweeteners other than sugar are added to keep thefood energy (calories) low, or because they havebeneficial effects for diabetes mellitus and tooth

decay and diarrhea.

Thickeners

Thickeners are substances which, when added to the

mixture, increase its viscosity without substantiallymodifying its other properties.



Conclusion

Additives are used to achieve one or thecombination of four purposes

1. To maintain or improve the nutritional value

2. To maintain the freshness

3. To add in process or preparation

4. To make food more appealing

Without additives or preservatives, some food would soon

spoil or it would be taste bland. If some foods were notmade storable,, food would be waste. Also, if some foodsare not stored properly, they can cause illnesses.



Some of the general categories of additives

(chemicals) that benefit food include preservatives ,

nutritional additives, color modifiers, flavoringagents, texturing agents, and aids to processing.

Over the year the chemicals have been added tofood unacceptable reasons, including.

To disguise inferior products

To deceive the consumer

To provide otherwise desirable results that lower

nutritional value To replace good manufacturing practices

To use in amounts greater than are necessary



References

Documents

Preservation by Food Additives