In this guide 6 sections
Weigh every intake lot and note its moisture. For each run, record the feed, then weigh the flour, semolina, bran and other by-products, and book the difference as loss. Compare yield by lot and supplier every week, and moisture and shrinkage losses will start to show.
Weigh and label every intake lot
Yield starts at the weighbridge. Record the truck number, gross weight, tare and net weight on the ticket. Draw a sample from several points in the load, not just the top of the truck.
Test the sample before the grain enters a bin. A moisture meter reading, a test weight and a look at broken kernels and foreign matter tell you more than the supplier’s word. Give the lot a number and keep the sample sealed for disputes.
- Supplier, grain variety and truck number
- Net weight from the weighbridge ticket
- Moisture reading and test weight
- Foreign matter and broken kernel notes
- Bin or silo the lot was emptied into
Record each run from first bin to last bag
A run is the unit of yield. Give it a number, start and end times, and the lots or blend that fed it. Note the water added at tempering and the hours the wheat rested before milling.
Take the feed weight from the flow meter or the batch scale. Then weigh the outputs where they are bagged: first grade flour, second grade, semolina, bran and the pollard or shorts. Weigh the cleaning stage waste too.
Never estimate by counting bags. Bag weights drift. A fifty kilo sack from a tired packer may hold less than the label says, and across a month that gap eats your margin.
- Run number, shift and miller on duty
- Feed weight and tempering water
- Weight of each product and by-product
- Cleaning waste, screenings and stones
- Scale used, with its last calibration date
Book the loss, do not hide it
Loss is feed weight minus everything you weighed coming out. Some of it is honest. Moisture leaves as vapour, fine dust goes through the aspiration system and a little spills at transfer points.
Separate the loss into two lines. One is cleaning loss, which belongs to the lot and the supplier. The other is milling loss, which belongs to the plant. Mixed together, they blame the wrong party.
Check scales weekly with test weights. A scale that reads light turns a good run into an invented loss. Mark each scale with its last check date.
Compare yield by lot and by supplier
After a few weeks, the sheet answers questions you could not answer before. Which supplier’s wheat gives the most flour per tonne? Which lots lose weight between the weighbridge and the first mill passage? Which lot arrived damp and dried out in the bin?
Judge a supplier on three or more runs of the same variety. One run can be thrown off by a worn roll, a bad sieve or a new miller. Use the figures when you renegotiate. Agree a moisture limit and a test weight floor on the purchase order, and state what happens to the price when a lot misses them.
- Flour extraction by lot, run and supplier
- Weight lost between intake and cleaned grain
- Bran and pollard share by variety
- Runs where loss stands out against the average
Start with one sheet and one line
Begin with a single printed sheet at the weighbridge and one at the mill. Run it for two weeks on one line. Compare the totals against your stock count of grain and finished goods.
If they differ, trace the gap to a scale, a missing ticket or a by-product that was never weighed. At the next Monday meeting, put the three worst lots on the table. Ask where each one went wrong. Then repeat the exercise a week later.
Intake lot and run yield sheet
A one page sheet in two blocks. The intake block has columns for lot number, supplier, variety, gross, tare, net, moisture and test weight. The run block has run number, feed weight, tempering water, each product weight, by-products, cleaning waste, loss and extraction, with a line for scale check date.
Open a blank worksheet to printQuestions owners ask
What is yield in a flour mill?
It is the weight of saleable products, mainly flour and semolina, divided by the weight of grain fed to the mill. By-products such as bran are counted separately, because they sell at a different rate.
Why does my yield change from lot to lot?
Moisture, test weight, foreign matter and variety all change what comes out. Damp lots lose weight in drying and tempering, and poor test weight usually gives less flour from the same tonne. Wheat from a wet season behaves differently from the same variety in a dry one.
How often should I calibrate the scales?
Check the weighbridge and bagging scales weekly with certified test weights, and after any repair. Record the date and the reading on the sheet so a drift can be traced to a date and a scale. Keep the test weights locked away from the shop floor.
Can small mills do this without software?
Yes, on paper at first, and many mills start that way. Software helps once you have many suppliers and runs, because it joins intake lots to runs and flags weak lots without someone retyping the numbers.