Steps To Obtain Turmeric (Curcuma Domestica) Ethanolic Extract Using Rotary Evaporator
A step-by-step guide for preparing turmeric raw material, extracting it with ethanol, and concentrating the extract using a rotary evaporator.
Preparation Of Raw Material
Washing
Weigh 5 kg of fresh turmeric rhizomes with approximately 80% moisture content. Wash thoroughly with running water, then perform a final rinse.
Slicing And Drying
Thinly slice the rinsed turmeric rhizomes and allow them to air-dry.
Grinding
Once completely dry, grind the slices into a rough powder suitable for maceration.
Extraction Procedure
Method
Perform the extraction using a cold maceration technique.
First Maceration
Combine 1 kg of dried turmeric powder with 10 L of ethanol using a 1:10 w/v ratio in a sealed container. Allow the mixture to macerate for 24 hours.
Filtration And Repetition
Filter the macerate to separate the liquid extract from the exhausted turmeric powder. Repeat this entire maceration process in triplicate, three times total, using fresh solvent each time to maximize yield.
Rotary Evaporator Procedure
Sample Preparation And Setup
Fill The Evaporating Flask
Pour turmeric ethanolic macerate into a 1-liter evaporating flask. Ensure it is filled to a maximum of half its volume to maximize the surface area for evaporation.
Attach The Flask
Connect the evaporating flask containing the turmeric macerate to the vapor duct.
Secure With Combi-Clip
Secure the connection using the Combi-Clip. Do not overtighten it, as the system will tightly seal itself once it goes under vacuum.
Set Parameters On The Interface
Set the parameters based on the thermodynamic properties of ethanol as follows:
Initiating The Distillation
Turn on the chiller: Start the cooling system and verify coolant flow.
Turn on the heating bath: Turn on the heating mechanism.
Start slow rotation: Begin rotating the flask slowly.
Engage the vacuum: Press “Start” for the vacuum pump on the interface.
Submerge and accelerate: Lower the rotating flask deeply into the heating bath, then increase the rotation speed to 280 rpm.
Monitoring The Evaporation
Monitor Condenser Loading
Watch the distillation rate through the ethanol droplets or by feeling where the condenser gets warm.
Check Condensation Height
Ensure the condensation line does not exceed 75% of the condenser height.
If Too High
Slightly increase the pressure.
If Too Low
Slightly decrease the pressure.
Achieving A Concentrated Extract
Once the ethanol has evaporated to the desired concentration level, stop the evaporation process.
Stop the rotation speed.
Turn off the vacuum and aerate the system until it returns to atmospheric pressure.
Raise the flask out of the heating bath.
Turn off the heating and cooling systems.
Collect the extract from the flask.
Final Collection
Carefully remove the Combi-Clip and detach the evaporating flask containing the thick and concentrated turmeric extract. Collect the extract for further use.
Detach and empty the receiving flask containing the recovered ethanol, so the unit is clean and ready for its next use.
