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PRESERVATION

PRESERVATION. From foukeffa.org Written by Teri Micke Ag Student Texas A&M GA Ag Ed Curriculum Office To accompany the Georgia Agriculture Education Curriculum Lesson 02471-21.2 June, 2002. WHAT IS PRESERVATION?. the treatment of food to keep it from spoiling. PALATABLE.

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PRESERVATION

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  1. PRESERVATION From foukeffa.org Written by Teri Micke Ag Student Texas A&M GA Ag Ed Curriculum Office To accompany the Georgia Agriculture Education Curriculum Lesson 02471-21.2 June, 2002

  2. WHAT IS PRESERVATION? • the treatment of food to keep it from spoiling

  3. PALATABLE • an agreeable taste and/or texture

  4. CONDUCTION • heating through direct contact • example: roasting marshmellows, grilling hamburgers on stove top

  5. CONVECTION • heating through water or air • example: boiling water, using oven

  6. RADIATION • heated through electromagnetic spectrum • example: microwave

  7. PASTEURIZATION • destroy pathogenic microorganisms but not spoilage microorganisms • example: milk

  8. TYPES OF PRESERVATION 1. canning - around for over 200 yrs 2 ways a. hot fill - heated before put in can b. canner’s brine - liquid (sugar/salt mix) added

  9. 2. Refrigeration - above freezing point 28 to 65 degrees F; short term storage 3. Freezing - actually freezing the water in the food

  10. 4. Drying a. mechanical: heat (sunlight), wind, smoke/heat examples: grapes to raisins, meat to jerky b. freeze drying: used by astronauts, just add water examples: milk replacers

  11. c. chemical drying add salt and sugar example: ham

  12. 5. Fermentation - involves microorganisms (yeast, mold, bacteria) 2 ways: a. aerobic: with air b. anaerobic: without air

  13. 6. Irradiation: expose food to ionizing radiation like x-rays, makes food sterile veg/spices easy to treat meats hard to do, but they are using on poultry

  14. 7. Food Additives examples: Salt Na or Ca - inhibit mold Sorbic acid - inhibit yeast/mold, used in cheese and fruit drinks

  15. Benzoic acid/sodium benzoate - candied products BHT/BHA - preserve fat in meat Citric acid/tartaric acid - antioxidants (traps oxygen)

  16. WHAT HAPPENS WHEN FOOD FREEZES?? Example: Tomato the water in the tomato freezes and forms ice crystals which act like sharp pieces of glass and puncture cells, the slower the freezing the larger the crystals

  17. WHAT IS FREEZER BURN? • it’s the loss of water from the frozen food

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