| 摘要 |
PROBLEM TO BE SOLVED: To provide a quick freezing method suitable for freezing preservation of preference beverages such as soft drink, and quick-frozen ice. SOLUTION: After pre-cooling of a sample down to 2°C, temperature drop transition is continuously measured. Time dt until a temperature difference (dT) between the start temperature (2°C) and sample temperature reaches 90% of a temperature difference (ΔT) between the start temperature (2°C) and refrigerant temperature (dT=0.9×ΔT) is measured and is defined as temperature drop speed (dT/dt). It is revealed that at any refrigerant temperature levels, in the condition of dT/dt≥0.02 (°C/sec), variation of both concentration difference characteristics and melting start time characteristics decreases. It is revealed that in particular, this tendency is remarkable in the condition of 0.09 (°C/sec) or more. COPYRIGHT: (C)2010,JPO&INPIT
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