FDSC 310 Lecture Notes - Lecture 5: Cooling Load, Anatomical Terms Of Motion, Sensible Heat

• School: McGill University
• Department: Food Science
• Course: FDSC 310
• Professor: Ramaswarmy

Document Summary

Lecture 5- cooling:basics, cooling rate, half cooling time. Cooling/precooling lowering of produce temperature from field to storage conditions. Sensible heat: results in a change of temperature q=mc delta t. Latent heat: results in change of phase (state) q=ml. Field heat: heat content of harvested produce above storage temperature or heat to be removed to bring produce temperature from field to storage. Vital heat: heat of respiration (respiration rate, heat) x (quantity) x (time). Advantages of cooling/precooling cooling quickly brings down respiration rate, transpiration rate, microbiological, ethylene, chemical activity. Cooling helps in cold storage design, reduces heat of respiration, reduces load on cold storage. Asap, asaf. cooling by air, water, ice, dry ice, ln. How much to cool calculated by rate of heat removal = quantity/time=kj/s or kw. Unit for refrigeration capacity: ton (rate) heat needed to freeze one short ton (2000lbs) of water at 0c in 24h = q/t.