Since i have not really got anything new to post up on my blog.......
and the last post that ms zhang will read will contain nothing amazing.

I have decided to have another post that includes the links for some new websites i have found that talk a bit about mould and preservatives.

I also still need to find the difference between mould and bacteria.
Now to hop to it

THE LINKS

http://www.epi.state.nc.us/epi/oii/mold/grow.html

http://natural-products.suite101.com/article.cfm/salt_as_a_natural_preservative


"Why is Salt Used as a Preservative?
Learn How This Important Preservative Actually Works
Many people use salt as a preservative without knowing how it works. This article explains why, so that you can have a better understanding of the preserving process
Salt has been used through the ages for the preservation of food. Many people will be familiar with products such as bacon, ham and pickled vegetables. All of these products use salt as the preservative. So why does it work? And how can salt be used as a preservative in natural products?
Antibacterial Properties
Salt is considered to be an antibacterial. That is why it is good at preserving products as well as food stuffs. Why is this so? Well, anything that is called antibacterial is called so because it inhibits the growth of bacteria. These bacteria feed off your product and cause it to spoil. Bacteria need a wet environment to grow in. Salt prevents the watery environment the bacteria need to thrive. This is because salt is very good at dehydrating and absorbing the water from anything it comes into contact with. Upon contact with a bacterial presence, salt will start to absorb water from through the cell walls and effectively kill the living organism.
Mould Prevention
Salt can also be used when you are preserving a product via fermentation. The salt will inhibit the growth of moulds and yeasts. While some moulds and yeast are certainly needed during the fermentation process, by using small amounts of salt, it is possible to regulate and stabilise this process.
It is only possible to do this though if you are using salt that does not contain ‘free-flowing’ agents or iodine. Both of these chemicals will prevent the salt from doing its job correctly. Therefore, when you are shopping for a salt to use as a preservative, it is important to use a salt that is listed as being free of both chemicals. By purchasing ‘pickling salt’ or ‘kosher salt’, you can be free in the knowledge that neither will contain these chemicals as both of these products are free from any additives. Once again, salt is effective in the fermentation process because of its dehydrating effects. This time though, it is used not to dry the product, but to help let any juices fun free, which are needed in fermentation.

By now it is easier to see why salt has been involved in so much superstition throughout history. It has been used by many vastly different religious groups to protect both individuals and buildings from evil. They did not have the scientific evidence to explain why salt kept food edible for miraculous amounts of time, but they associated the salt with strong magic. That is why it is used to protect and heal in sympathetic magic."

http://www.globalgourmet.com/food/special/2001/comforts/preservation.html


"Salt, Sugar, Acid, and Dryness:
Natural Preservatives

When foods are very salty or sugary, they draw water out of bacteria, which either kills the bacteria or keeps their numbers down. Thus sugar and salt keep in the pantry indefinitely. Many sweet or salty foods will also keep for long periods. Many types of candy, stored in a tightly closed container, last for a long time on the shelf. Honey and pancake syrups keep without refrigeration for about a year; molasses will last for six months. Genuine maple syrup, however, tends to mold and eventually ferment in the pantry (after it is opened), as it is less concentratedly sweet than these others.
Acidity and dryness also discourage bacteria. Vinegar, with a pH ranging from 2.4 to 3.4, is too acidic to be friendly to bacterial growth, so you ordinarily need not refrigerate it, and it will last safely on your pantry shelf for as long as a year. (But see the book.) Pickling and brining use a potent combination of salt and vinegar or other acid to preserve and flavor foods at the same time. Nowadays we refrigerate our pickled foods after opening them so as to keep them crisper and better-tasting. But pickles always used to be stored in the pantry-in the pickle barrel or jar-and some stores still sell pickles from the barrel, at room temperature.
Meats such as bacon and ham are still sometimes salt-cured (and sometimes are both salt-cured and smoke-cured, smoke being another "natural" preservative). Cured meats last longer than fresh meats, but all meats are such desirable homes to bacteria that they must be refrigerated even after curing to keep them safe.
Because dryness is antimicrobial, flours, mixes, pasta, rice, and dried beans may all be stored in the pantry. Molds, however, may afflict dried foods if your pantry gets too humid.
Foods containing enough alcohol, a general disinfectant, can also live long on your pantry shelves. It is the presence of alcohol that keeps your vanilla, almond extract, and other flavoring extracts, as well as alcoholic beverages, safe for long periods on your shelves without refrigeration."

http://www.tpub.com/content/armymedical/MD0703/MD07030071.htm


"3-12. PRESERVATION BY VINEGAR
The preservative action of vinegar is based upon its acetic acid content.
Pathogenic bacteria are rapidly destroyed in pickle solutions containing three percent acetic
acid and three and one-half percent salt. Vinegar is important as a preservative, because it
reduces the thermal death time of microorganisms and either inhibits or kills microorganisms,
depending on the concentration used"

http://www.essays.cc/free_essays/f4/rsk224.shtml


"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. Page 4 Graphics page 5 Introduction: 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. Page 1 Conclusion: 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 have included the parts that I find relevant to my experiment, why the preservatives are supposed to work and how they work.

I still need to to a tonne more of research on mould and bacteria. So, stay tuned
I'll probably repost on the weekend

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