MICR-4070 Lecture Notes - Lecture 10: Food Preservation, Magnetic Ink Character Recognition, Pigment
Document Summary
Micr 4070: lecture 10: physical methods of food preservation. Utilize physical treatments to inhibit, destroy, or remove undesirable microorganisms without involving antimicrobial additives or products of microbial metabolism as preservative factors: destroy microbes in canning and radiation, removes microbes by filtration. Natural ice blocks cut from frozen lakes, stored and used to preserve foods (early. Domestic refrigerator was developed by linde (ca. 1874), & commercialized by 1890: microbes at lower temp will start to grow slower (still above freezing) and below freezing will begin to die or stop growing. Microbes need enzymes to catalyze activities (temperature dependent: increases in temperature cause increase in the growth rate, if you lower the temperature enough, enzymes will become denatured, and the microbes will stop growing. 65% of all foods consumed are frozen or refrigerated (usa) Chilling: foods held on ice: storage life of a few days, can be very convenient, but not very accurate and cross-contamination is possible.
