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Microorganisms in a Macro World (part 3)

mbeall

CHIN, Gatineau, Quebec

6. Chemical additives

  • Addition of organic acids
Only a few organic acids are legally accepted as food preservatives. Sorbic and propionic acids are used to inhibit the growth of fungi in bread.
  • Nitrites and nitrates
Nitrites and nitrates are added to meat to preserve their color and inhibit the growth of anaerobic bacteria. This practice is considered controversial because of the possible role of nitrates and nitrites as mutagenic or carcinogenic agents.
  • Substances produced during manufacturing
In some cases, chemical preservatives are produced during the manufacturing of the product or during the preservation process. Sauerkraut and pickles, which are prepared by fermentation, are thus preserved by acetic (vinegar), lactic, and propionic acids produced by the fermentiscible microorganisms. Smoking food generates antibacterial compounds that penetrate and preserve the meat.

Armand-Frappier Museum


© Armand-Frappier Museum, 2008. All rights reserved.
Learning Object Collection: Zoom in on Microorganisms
Learning Object: Our defenses against germs
Institution: RCIP-CHIN