Freeze Drying Tips
Most of us should have heard of freeze dryer lyophilizer. This machine is widely used in food and pharmaceutical industry: freeze-dried pet treats, freeze-dried snacks, freeze-dried fruit, to list just a few. People even buy one for daily use, and this really helps a lot in improving life quality. But do you know some freeze drying tips that can help better to get expected products and protect this usually not-cheap machine? Hawach lists some for your reference.
Freeze Drying Tips — before operation
a. The freeze dryer must use an independent power socket with good grounding.
b. The distance between the lyophilization machine and the wall is ≥30cm.
c. It is forbidden to place other heat dissipation equipment near the machine, which may cause the refrigeration system to fail to dissipate heat.
d. After the equipment is placed steadily, press down the caster holder.
e. Ensure the surrounding temp. is around 5-30°C before switching on the lyophilizer, and this can help to prolong the life of its compressor.
f. Start the freeze drying process after the machine has been on for 15 minutes. The purpose is to pre-cool the cold trap and pre-heat the vacuum pump. Only in this way can the machine work in a better condition
Freeze Drying Tips — during operation
a. Before pulling a vacuum, plug the drain pipe and shut down the adapter system, otherwise, the vacuum pump will be damaged.
b. If the tray and external freeze-dried bottles are used at the same time, put the materials on the tray first, wait for half an hour, and then hang the bottles when the refrigeration temperature is -50℃ or -80℃ and the pressure is 30mTorr, so as not to melt the materials inside the bottles.
c. The materials must be frozen well. The pre-freezing temperature should be below -30℃. And for samples that are not easy to freeze such as non-aqueous solubles or 80% + high-concentration sugars, the tempt. should be below -80℃. The pre-freezing time is not less than 24 hours, preferably more than 48 hours.
Freeze Drying Tips — after operation
a. Open the quick inflation valve of the freeze dryer, and then turn off the switch of the vacuum pump to let the air slowly enters the cold trap.
b. Turn off the button of the vacuum pump and refrigeration system of the device, and unplug the power cord if you are not going to use it again recently.
c. After the ice in the cold trap turns into water, the water needs to be drained from the quick inflation valve port. The draining operation is similar to that of inflation; (If there is a defrost function, press the defrost button to accelerate the dissolution).
d. Clean the moisture and impurities in the cold trap, and properly maintain the equipment;
e. For multi-bottle types, the rubber valves should be closed one by one and the freeze-dried bottles should be removed, and then the shutdown operation should be repeated.
The above is all the freeze drying tips. In order to ensure its normal operation and good product quality, these tips are indispensable. Hope you like this article.