食品速冻技术与冷链发展状况.ppt

1、食品速冻技术与冷链发展状况,年人均消费水平,冷冻产品状况,易腐食品低温运输状况,易腐食品低温贮藏状况,易腐食品低温贮藏状况（上海）,冻结速度对食品质量的影响,冻结与解冻过程特点,溶质对冻结与蒸发温度的影响,稀溶液中水的蒸气压比纯水蒸气压低,在压力相同条件下，稀溶液中水的沸点高于纯水的沸点。,在压力相同条件下，稀溶液中水的冰点低于纯水的冰点。,研究热点问题,速冻食品的质量问题 超高压速冻技术 快速冷冻技术 部分玻璃化技术 介电解冻技术 实现上述技术的装备 冷链建设与工艺管理问题,螺旋速冻机,螺旋速冻机,单体流化速冻机,单体流化速冻机,低温介质速冻机,低温介质速冻机,低温介质速冻机,隧道式速冻机,

2、氢与电负性很强，且具有独立电子对、原子半径又较小的原子可形成氢键（如氮、氟）,部分玻璃化技术,部分玻璃化技术,冷冻稳定剂较高的Tg,冷冻保护剂 较强保水性,常用添加剂对粘度影响,玻璃态热力学特征,果蔬田间热与呼吸热,The respiration rate and the production of CO2 depends mainly on the storage temperature,风冷,风冷,负压风冷,水冷,水冷,水冷,冰冷,蒸发冷却,Straw packinghouse,真空冷却,真空冷却,装货,移动式真空冷却设备,Room,Comparison of Produce Effect

3、s and Costs for Common Cooling Methods,风冷运输,风冷运输,低温运输,国外应用示例,Product arrives from the field on line trucks. Some is then cooled by icing and some is vacucooled.,Vacuum cooling involves placing cartons of produce in a chamber where the atmospheric pressure is lowered.,国外应用示例,This causes the boiling p

4、oint of water to drop and it is boiled off. Cold water is simultaneously added to the cartons so the product emerges cold and undamaged.,Regular icing involves packing each carton of produce with ice. At 25 pounds per carton, we use tons!,国外应用示例,Bonipak Produce Company can manufacture 300 tons of ic

5、e each day and we can store 400 tons.,When large quantities of product come into the cooler over a short period, we cool the produce in our Air Tunnels. We have 8 tunnels, which hold 14 pallets of produce each. The cartons are covered with a tarp and cold air is then forced through the holes in the cartons.,国外应用示例,Over a period of hours, the produce is slowly cooled to the desired temperature. The