Friday, August 3, 2007

The Weapons

Vinegar. It is a powerful antibacterial. It is a low pH acid. Most bacteria do not survive in that environment. Can be seen as an ingredient to its use in pickling. Even more potent when combined with salt.

Acid. Includes vinegar, citric acid, and others.

Salt. It absorbs the water in and on the food. Without water, bacteria cannot live or multiply. In high concentrations, it can also pull the salt right out of the cells of the bacteria and killing it.

Sugar. It absorbs water similar to salt. The concentration must be very high to be effective. Mostly can be seen in candies that have an extremely long shelf life.

Heat. It kills. Used to sterilize containers, kill bacteria in food in the containers, and pasteurization.

Freezing. Freezing temperatures either kill the bacteria or put them into "hibernation". Most foods will last forever in the freezer if it weren't for freezer burn.

Smoke. I have no idea how but smoke kills bacteria as well. Seen in smoked meats.

Dehydration. Removing almost all the water in the food will prevent bacteria from growing. Used in jerky and other cured meats.

2 comments:

Chaia Milstein said...

Tom, I had no idea you were so OCD until now. Please keep updating!

Greg said...

You're not quite right on sugar, salt and smoke. with sugar and salt, its not about the dehydration (water absorbtion) they cause but that they produce environments that are toxic to life. Though much microbiotic life (harmful or otherwise) actually requires and thrives in mild salt or sweet environments, you jack up that concetration and you create a toxic environment, not unlike a person having high salt or sugar concentration in their bodies. As to smoke, it fills the food with chemicals that are toxic to microbiotics and thus pretty much works the same as high concentrations of salt or sugar. But yes, toally coat something with salt, and it will dehydrate it as is done with things like cod but that creates a very nasty product whewreas only small concentrations are needed to pickle even fish. Jams and Jellies are very well perserved (hence being called preserves) and their sugar concentrations are not as high as you seem to think they would need to be (but they do also have fairly low/acidic pH's as well).