Determining Freezing Times of Food with a Plate Freezer
Objectives and Learning Outcomes
Determine experimentally freezing points and freezing times for different food products, using a plate freezer.
Compare the freezing points and freezing times of different water content food products.
Examine the applicability of empirical formula to estimate freezing times.
Freezing is an excellent method for food preservation, because it reduces or stops the micro-organism action, chemical and enzymatic reactions and preserves the aroma, the nutritional value and other quality attributes.
During freezing storage, adequate package and the maintenance of lower and stable temperatures are essential factors for the preservation of quality and nutritive value of foods (Fellows, 1988).
Since damages caused in food texture and other deterioration changes, due to concentration effects, happen more quickly during the “critical phase” of the temperatures’ history (which occurs from –1 to –5ºC), the quick getting through this phase...
KeywordsHeat Transfer Coefficient Freezing Point Freezing Time Expansion Valve Freezing System
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