FOS 3042 Lecture Notes - Lecture 36: Modified Atmosphere, Staling
Document Summary
Important thing that came to long term preservation of foods in modern history. First commercialized in the 1920s in the us. Not as common in less developed countries (cant afford) Avoid temp deviations that come from people holding door open, lights, food items. Proper humidity: prevents drying or excessive mositure. Cold does not exist: just lack of heat. No bacterial growth below -9. 5c or -17f. Preserves for months to years depending on how cold the freezer is. Effects: limits microbial growth, retards metabolic, enzymatic activity like fruits, retards ripening, softening especially fruits, retards water loss and wilting (short term) compared with no refrigeration, prevents undesirable growth like sprouting in potatoes. Need to refrigerate soon after harvest of produce: pre-cooling (fresh produce, meats, a key factor in food quality and extension of shelf life. Modification r control of atmosphere (ca: fresh produce, meats, lower oxygen, increase co, extension of shelf life. Packaging materials play a key role (map) modified atmosphere packaging.