Preserving is a means of storing, food both “raw” and cooked

for a future date. When you preserve you are following centuries of an old

tradition of “putting food by”. In order to do this, you have to seal the food

in an airtight container and process it in such a way that the four main

spoliers- enymes, molds, yeast, and bacteria are removed and your food is

safe to eat.

Preservatives are something used to preserve food. Natural or chemical

substances are added to food to inhibit spoilage; also, to protect food from

decay or fermentation. Three things that will prevent the growth or slow

down the growth of these spoilers: heat, cold and the use of acidity in the

product. The point of preserving is to slow down the activity of

disease- causing bacteria and to kill the bacteria all together. Most of the time

preserving kills something called enzymes which is naturally found in the

food. Enzymes makes the food spoil or discolor faster. An enzyme is a

special protein that acts as a catalyst for chemical reaction, and enzymes are

fairly fragile. Preserving protects food from microbes and other agents.

Preservation keeps good appearance, flavor, texture, and original nutritional

value. In addition, some things that make food spoil are microorganisms such

as bacteria, and fungi. Atmospheric oxygen can react with food constituents
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that causes rancidity or color changes.


Salt has been used, since ancient times, especially for meat, as a

preservation technique for preserving foods. Salted meat can last for years.

The salt enters the tissue and in effect binds the water, inhibiting the bacteria

that causes spoilage. The salt restricts to tiny concentration and protects food

from yeasts and molds. Salt has anion from hydrochloric acid. Salt is also

known as sodium chloride. The salt draws out moisture and creates an

environment inhospitable to bacteria.


Sugar is important. It is an organic compound called

carbohydrates. It is sweet in taste and used to sweeten other things.

The sugar is in a form of white or clear when it is refined from a raw state. It

dissolves in water very easy turning water sweet. Sugar is used as natural

preservative. The sugar inhibits the bacterial growth after the food or products

have been heated. It keeps it from spoiling.



Lemon is part of Rutaceae family. It’s also known as a citrus fruit.

Lemons are grown in the mild climatic regions. The lemon is 30 to 45 percent

juice depending on the type and climate. The acid that the lemon has is

mostly from the citrus. The lemon is also used as a preservative, because of

the acid C6H8O7. Most foods other than fruits and tomatoes have a high pH

factor and are low in natural acid, but with the use of lemon, juice the balance

can be redressed. It is strong just like salt and it takes the moisture out of the

food to prevent spoilage and rotting. The lemon contains a lot of vitamin C.

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I am doing research about Natural Preservatives for my science project

for the George Washington Carver Since Fair. In this paper I will be talking

about the Natural Preservatives salt, sugar, and lemon juice. I will give you a

summary of what preserving is and some history about it. I found it

interesting to read. . In my paper I then go on talking about the three different

natural preservatives that I used for my project. Firsted I talked about salt,

sugar, and then lemon juice.

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In conclusion I would like to say I learned a lot. I enjoyed doing this

paper; I learned about the natural preservatives salt, sugar, and lemon juice.

I learned about the history of preserving and the three natural preservatives. I

learned about all different ways to preserve. If I had to carry this project over

in to another year I would have to think of a way to maybe carry the steps of

preservation to a higher level. I would probably chose three different natural


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1. Groiler Encyclopedia
Groiler Incorporated
Danbury, Connecticut -1993

2. Perfect Preserves
Michael Friedman Inc.

3. Rodalel’s Book Of Home Freezing
Rodale’s Press Inc.
Pennsylvania- 1984

4. America Online
WWW. Google. Com

5. Modern Chemistry
Holt, Rinehart, and Winston Inc.