Eating is an agricultural act - Wendell Berry

Monday, June 14, 2010

pressing engagements

those who remember the post from a month ago - growing sesame - til - yellu - would recall that this was specifically for oil.
although i had said, "we shall be converting this small quantity into oil and that's another post coming up in 2 months from now.", it is time to reveal the oil press.

also, i would draw the reader's attention to the edible oil warning issued over 2 months ago. chances that sesame oil being mixed with cotton-seed oil is very high. and cotton-seed oil uses BT seeds....

so it was an imperative to press our own oil.

DV navigated through the haystacks of google searches to latch onto this beautiful needle - the piteba oil press.

here is the full unit...the seeds are feed from the top (check the funnel). just left of the funnel is the crank which turns the screw encased in the horizontal red barrel. the metal cap on the right side of this barrel is the cake-extrusion point (you can see the snake-like extruded cake).
just below the barrel is the oil collection point (tumbler in the pic) and the glass bottle is the oil-based (kerosene or diesel) heating lamp.
we have only done a sample testing of the machine and after 3 iterations, successfully extracted the oil. while we will not refine the oil, we will refine the piteba oil press.

the crank has to be turned for the screw to turn and compress and squeeze the oil. in normal operations, the speed will be around 40 rpm and the oil-extraction rate is 2 litres an hour.

the oil is squeezed out of 2 slits on the lower side of the barrel and drips into the receptacle. below pic captures this quite beautifully.
the oil lamp is needed to heat the barrel. the temperature is expected to go upto 50-60 deg C. without this heating, the cake will just jam up at the extrusion point and it will take super human effort to turn the crank.

a close up, showing the cup that overfloweth.
notice the soot... we need to solve for that.

the oil will be mixed with some fine particles and appears dark when seen immediately after pressing.
but allow it to settle, it acquires the golden tinge of fine scotch.

it is now ready for consumption
since this is not 'refined' oil, it will not have much shelf life. remember that the 'refining' is merely to make the oil last longer in the stores, it is not purer!
freshly pressed oil will have to be consumed within 3 weeks of pressing.

highly recommended. stronger arms are a welcome side-effect.


siddharth said...

interesting! since you talk about refining the oil press, I wonder if it helps to pour back a small fraction of the pressed oil back into the funnel so as to reduce the effort required to crank the handle? Or does it mess up the operation completely?!

Unknown said...

I saw this weblink. The picture of manual oil expeller does not show the heating equipment. does it work without heating? The address is of Chennai.

Kishore said...

On the link I saw Jatorpha oil being extracted. Would this work for bio-diesel?

csm said...

sid - the chances that this will work is low. there is already oil. the non-heating jams up the cake exit points.

kedar - as ever, great link. will check them.

kishore - we have one press for non-edible also. plan to try that with some neem, pongamia soon. it is expecte to work.

FabFourties said...

Hi Sriram/Karpagam,

Congratulations on going on a path that you believe in and being an inspiration for others like me to attempt it. Thanks so much for publishing your experiences so that we can connect with you.

I would like to get one of this for our home use for edible oils. I would like to know if you are still using it and if yes - how is the performance. And can you please help me with the following questions.

1.Do you recommend it for others? We are primarily wanting it for edible oil for a household of 4.
2. How much time does it take for extraction of 1 litre of oil - say ground nuts and sesame?
3. Any maitenance issues that we should be aware of?
4. Should it be mounted on a strong base or will any free standing stool do?

Thank you so much for your time.

csm said...

dear fabfourites,

there was an intermediate lull since we did this posting as we were trying to solve the soot issue (important matter to be solved for all users).
after many attempts, we realised that a simple SS sheet with a circle cut out and wrapped perpendicularly around the shaft will simply solve the matter.
1. i would recommend for households.
2. approx 1-2 lits per hour.
3. only soot.
4. strong base preferred. you can use a temporary clamping system as well. when heated well, it does not require much force.

for more info write to sriramskd At gmail DOT com