FOS 3042 Lecture Notes - Lecture 9: Modified Atmosphere, Staling, Thermal Conductivity

• School: University of Florida
• Department: Food Science and Human Nutrition
• Course: FOS 3042
• Professor: Obadasi

Document Summary

Cold preservation: commercialized in the 1920s in the us, very important in developed countries. Not as common in less developed countries. Avoid temperature deviations (people, lights, food items) Avoid sweating (moisture condensation: usually between 2-7 degrees c (36-45 degrees f, preserves for days or weeks, some spoilage organisms can grow, mild form of preservation, effects. Retards water loss and wilting (short term) compared with no refrigeration. Prevents undesirable growth (sprouting: need to start refrigeration soon after harvest or slaughter. Key factor in food quality and extension of self life: modification or control of atmosphere (ca) Fresh produce, meats will have better storage when flushed with nitrogen. Packaging materials play a key role (map- modified atmosphere packaging: common changes during extended refrigeration. Freezing: -18 degrees c or -32 degrees f and below, no bacterial growth below -9. 5 degrees c, preserves for months to years, pure water freezes at 0 degrees c, frozen foods. Must be super cooled to below 0 degrees.