6.3 & 6.4 Using and Caring
for Your Processing Equipment

The Polisher

Directions

1. Ensure that the shutter outlet from the hopper is always closed prior to pouring the grain into the hopper, otherwise the grain could get jammed in the machine

2. Switch the aspirator on before switching on the polisher, to begin the process of drawing out the dus

3. Have a large trug under the polisher to collect the polished grain - it will fly quite widely. Never use a bag as this will be sucked up into the mechanism by the power of the aspirator

4. Once both machines are on, open the shutter outlet to half way
5. Before switching off the polisher and aspirator take away the bucket of newly cleaned grain and replace with an empty one, then shut off the aspirator and allow the polisher to continue until no more grain is coming out. A lot of residual rubbish (smaller seeds, light seeds, weeds, chaff) stay in the machine and will come pouring out once you shut off the aspirator. If it has weed seeds in it this can go for pig feed, otherwise put it back in with your supply of unprocessed grain

User Instructions

Disadvantages

A residual amount of grain would always be left in the polisher, causing contamination when we changed grains.

Area of uncertainty

You could adjust the tilt of the polisher and this would affect the speed that the grain moved through the machine, and presumably the amount that was left in the machine, however we never worked out what the optimum position was. John Letts recommended lowering the outlet level more and more as the brushes get worn, not that this was an issue for us.

Cleaning

It was useful to take the machine to bits a few times to understand how it worked, however this was a laborious way of cleaning the machine as it took a while to put it back together again and we needed a socket set. We also tried running a vacuum cleaner and sucking out the grain from the shutter outlet which was also time consuming. Running the machine without the aspirator for a few minutes at the end of polishing a particular grain cleared out approximately 60% of the residual grain. This didn’t matter if the next time we were polishing we were doing the same grain, however if we were introducing a different crop we opted for the purging regime.
See Checklist 4.2 - Food Hygiene Documentation and Procedures

The Flaker

Directions for rolling oats:

1. Ensure that the shutter outlet from the hopper is always closed prior to pouring the grain into the hopper to avoid oats jamming in the mechanism

2. Fasten a bag to the outlet to collect the flaked oats, using the handy leather belt with it’s hook and eye fastening. Don’t use a trug to collect the flaked oats as they will fly quite widely

3. Tighten the rollers as far as they will go and then open them by one 360 degree turn of the handle to release the rollers; you may have to experiment to get the distance right. You want the rollers as tight as possible without stopping the grain moving through, to flatten it as much as possible
4. Switch the machine on and open the shutter to the 2nd mark
5. Once your bag is full, close off the shutter and then switch off the machine
6. We put the oats back through the roller 3 times in order to get a rolled oat that was good for porridge; each time the oats would become a bit flatter and a little more broken up

User Instructions

Troubleshooting

• Because oats are high in oil they can get jammed in the roller, particularly on the third time through. Open the shutter wider (to mark 8) and open the rollers up 3-4 360 degree turns before starting the machine

• Get to know the different sounds of the roller. There is a distinct sound when the roller jams, and if you don’t turn it off quickly you will start to burn the rubber belt and it will smell! When this happens, quickly shut the shutter at the bottom of the grain hopper and immediately switch the machine off. Open up the rollers all of the way, then switch the machine back on; this should release the blockage. Once it has dislodged, switch the machine off and tighten the rollers back up otherwise you will have grain that hasn’t been rolled going through

• If this doesn’t solve the problem check that there isn’t a blockage in the outlet by removing the bag and looking underneath, you may need to poke the oats if they are jammed with a stick – watch your eyes! Ensure the machine is off!

As a last resort (which we never had to do) you will need to empty the hopper as much as you can and suck up remaining visible grain with a vacuum cleaner hose into the feeding hole, make sure the machine is unplugged (not just switched off). Open the front panel to reveal the belt and cogs, then you must find a way of dislodging the grain still between the rollers by moving the cogs (made of plastic) or the belt either forwards or backwards

• The other problem could be (I hope not) that you have burned out some/all of the belt and it is no longer tight enough to turn the cogs. There may be an adjustment on your machine to tighten it up again. Be careful when forcing the plastic cogs to 1) not break them and 2) not get your fingers stuck between them

The flaker doesn’t generally hold grain in the machine and therefore there isn’t risk of any significant cross contamination. Ensure that all of the grain has gone through the rollers before finishing a batch and check that there are no blockages between the rollers or in the outlet.

The Mill

1. Ensure that the shutter outlet (red knob) from the hopper is always closed prior to pouring the grain into the hopper, otherwise it could block up

2. Secure a bag onto the outlet to collect the milled flour, using the strap provided with the machine and ensuring it is sealed tight, otherwise the flour will get out and cover everything around in a fine layer of dust. There is also a bag directly above the outlet which allows for the expenditure of air pressure as the flour comes out; ensure this is secured before milling

Directions for milling fine wholemeal wheat flour:

3. Fill the hopper and switch the machine on

4. Open the outlet to release the grain between the stones. For wholemeal you may well be able to open it up fully

5. The first time you use the mill it is advisable to tighten the stones as far as they will go and then release by 1 x 360 degree turn. Use this as your starting point for setting the distance between the stones to get the right grade of milling. Close the distance between the stones, all the time listening to any change in sound. You want to get it to the point where you just hear the stones grinding on each other and then take it back a fraction, i.e. so the stones are as close together as possible but without grinding on each other.

6. Once you think that you have got the setting right, attach a fresh bag to the outlet and let it run for a few minutes then take a look at the flour coming out to check that you are happy with the quality

7. Once you are happy with your settings you can leave the mill to run unmonitored, remembering to change the bag before it gets too full

8. Before removing the bag of milled flour, shake out the top bag and bang the outlet chamber where flour will have gathered

Directions for Milling White flour:

1. Tempering is a practice designed to soften and loosen the bran but not the endosperm (starch) of the grain. Temper the grain by misting in 2-3% moisture 20 minutes before milling, mixed as thoroughly as possible

2. Let it sit for 20-30 minutes so that the bran soaks up the water, but not so long that it penetrates into the seed. This improves the extraction rate; the bran will separate from the grain in bigger bits, which can be sieved out more efficiently

3. Sieve the flour immediately after milling. If the bran is not removed the moisture will dissipate into the flour and reduce its shelf life. Tempering isn’t advisable unless the flour is going to be sieved, or the wholemeal flour is going to be used immediately

User Instructions

Troubleshooting 

• Listen out for changes in the sound of the mill

• Be careful to not have the stones so close together that they create friction with each other; as well as cooking the flour this will wear them out quickly.   You will know immediately as the smell of the burning stones is quite strong 

• Overheating the flour during milling will destroy/deactivate certain enzymes in the grain that are temperature sensitive, which can affect the fermentation process. Temperature is affected by:

  • The output of the mill

  • The moisture of the grain

  • The sort of grain (soft wheat, hard wheat)

If you go too fast, the temperature will increase, if the grain is not dry enough, the temperature will also increase. Don't worry about the temperature of the body of the mill - it is not the temperature of the flour.

• If the machine suddenly cuts out for no obvious reason it may be that the timer has run out, simply turn the timer and the mill will switch back on again

• If you forget to remove the bag and it over-fills, the flour will back-up into the machine. If this happens make sure that you clean out the outlet, checking that it is clear before you start up again

• If the voltage goes over the red line marked on the dial then switch off the machine, let it cool down and reduce the volume of throughput of grain entering the mill by tightening up the red knob. If this doesn’t help you may need to widen the gap between the stones slightly

Output

• An optimal output is between 60 and 70kg per hour, with the amp not going over 5.3 Amp. Initially we were running the grain through the mill very slowly in an attempt to keep the temperature down as low as possible, however we discovered that opening the outlet up to allow the grain through at a faster pace didn’t appear to increase the temperature significantly and it greatly increased our throughput, making our time spent milling more cost effective 

Cleaning

• We were advised by Samap not to put oats through the mill because of their high oil content, however we decided to ignore the advice because of the relatively small amounts that we were milling to make coarse oatmeal and oat flour. We would always run wheat or peas through the mill after milling oats as this would help to clean the mill

• We would regularly take the mill apart to clean the stones, particularly after milling oats. Flour would build up in the indentations in the stones and we found a rounded teaspoon handle and a vacuum cleaner were the best tools to remove this build up. Dried flakes of compacted flour would also build up around the cylinder, holding the mill stones

• Be very careful when removing the top mill stone to keep the thread level - unscrew the black knob to release the lock on the stones and then use the knobs opposite each other to unscrew the stones. As you start to get closer to the end of the thread, the thread will become exposed. It is covered in grease so be careful when manoeuvering the stones not to get this on you. Get someone else to help you lift the top stone and hopper out of the chamber and invert it so that the weight is resting on the rim of the hopper. When you insert the top stone back be very careful to get the threads aligned to avoid cross-threading, and tighten gently until you are sure that they are

Sieve

Directions for Sieving Flour

Our model of Farley Green Sieve had a stacking system where we could have up to two sieves in operation at once.

The coarse sieve sat on top and was used for all flours and the finer sieve was added to the stack when we were sieving to produce white flour.

 It is a very simple piece of machinery to use.

1. This is the dustiest job! Put your dust mask on

2. Ensure that the correct combination of sieves are set up; coarsest at the top and finest at the bottom.The highest outlet in the stack will discharge the coarsest fraction and the lowest outlet will discharge the finest fraction

3. Ensure that you have appropriate trugs collecting the flour and waste as it comes out of the various outlets - you will need a large trug for collecting your final flour and, if sieving white flour, a large or medium one for the bran and a small one for the very coarse bran and bits of chaff  

4. Pour the freshly milled flour into the top of the sieve and switch the machine on. You can leave the sieve whilst you attend to other things, just keep an eye on the trugs to ensure you don’t over fill them

Troubleshooting

• We found a fault in the design of the Farley Greene Sieve; the outlet to the coarse bran (the waste) needed a piece of cardboard lining it to raise the height, as unsieved flour was escaping over the top of the brim and ending up in the waste trug

• We found that when sieving for white flour we lost a lot of potentially good flour in the bran and we would need to put it back through the sieve 4-5 times  

• On John Lett’s recommendation we put some small blocks of plastic, not too heavy, into the finer sieve when it was in use. They helped move the bran around and stopped the sieve from blocking so much. If you can’t stack both of your sieves put the flour through the coarse mesh first to remove the coarsest bran (this shakes it up and loosens the flour), then change the sieve and run it through a finer one. It will greatly help the extraction rate

• If the temperature is cold in your processing unit and your flour is warm, condensation may form on the sieve and this dampness will reduce the flow of flour. If this happens, dismantle the sieve’s layers and clean everything out

• We had problems with the quick release settings that held the physical sieves in place; the metal chambers of the sieve unit were not totally symmetrical and getting the sieves aligned proved fiddly. Farley Greene sent us some replacement closure fittings but these weren’t quick release

• We didn’t sieve our pea flour and as a result it had some coarser particles in it - the outside of the pea. When we compared it to Hodmedods flour we realised that it would have been better sieved; pea flour is very fine and friable

Cleaning the Sieve

• Take apart all of the sieve’s layers

• Gently knock remaining flour out of the sieves. A steel brush may help to remove bits of chaff stuck in the sieve holes

• A soft paintbrush proved useful for cleaning out the metal chambers and outlets of the sieve