Batch grain dryers can help boost specific weights

With three-quarters of his wheat sold for biscuit-making, Lincolnshire grower Dunmore Hind is particularly focused on ensuring his grain meets spec to achieve the premium.

But last year’s poor growing season made that a challenge. While most other quality parameters weren’t an issue, it was bushel weights where the 2012 crop struggled.

“As a bare minimum we need to be over 70kg/hectolitre, but we’ve been struggling to get anywhere close, averaging about 65kg/hl,” he explains.

“We’ve never had an issue before – we’re usually well over 72kg/hl. Neither my father or our agronomist can remember a year like this.”

With such a marked gap, Mr Hind was facing a double hit. First off, the loss of the biscuit-making premium (at around £15/t) and secondly in deductions for the crop’s low bushel weight, even as feed wheat (a further £15/t).

Drastic action was required. Having heard about other farms having success in bolstering grain weights by running crops through a recirculating batch dryer prior to loading, Mr Hind decided to give it a try.

“We had two 30-year-old Opico 12t GT dryers as our ‘get-out-of-jail-free-cards’ for really wet grain when the on-floor drying can’t keep up, and so we’ve got plenty of experience of the polishing effect they can have.

“When we tried them, they were bringing the sample up from 65kg/hl to well over 70kg/hl.

Last autumn, he decided to splash out on a 29t capacity machine to provide the output necessary to process the 1,800t of Zebedee soft wheat in store. With just that work, the unit has almost paid for itself.


 Biscuit-making premium   £15/t
 Avoided bushel weight penalties    £15/t

Diesel (@ 65ppl)

 70-litres/hr for 1hr  £1.89/t
 Elecricity (@ 11p/unit 200 units in 4hrs £0.92/t
Labour and loader 15 minutes per batch £0.42/t
Margin £26.77/t
Total net saving £26.77 x 1,800t= £48,186
29t OPICO Magna dryer with dust extractor £57,000

*figures are based on 24t batches

NB – These figures do not account for the fact that the grain would anyway need to be dried down by 2% to meet spec and the additional value of that.


Typically it takes four hours to get the sample up from 65kg/hl to an acceptable level, although sometimes it simply isn’t possible to get it beyond 70.5kg/hl so deductions of between £1-3/t have to be accepted.

There’s very little actual weight lost from each 29t load. It’s mainly just light, bulky dust and chaff that adds up to between 150kg and 200kg per batch.


“Last year’s crop is undoubtedly the worst we’ve seen for specific weights,” says Openfield’s Kate Reynolds.

But a few simple steps can make a big difference. The most impressive results have come about with growers using recirculating batch dryers, according to Ms Reynolds.

“It’s possible to get grain up from below 65kg/hl to 68-69kg/hl, but pushing it above that isn’t always achievable, so you may just have to accept £1-2/t deductions.

“However, we can always find a home for those crops. To minimise financial losses, talk to your merchant to make sure the right wheat ends up at the right home.”

She strongly advises against blending good quality samples with poorer crops as this will only dilute the value, reducing the premium potential of up-to-spec grain.

However, growers confident that crops now in the ground will carry better bushel weights could consider “over-yearing” last season’s poorer quality grain with a view to blending it with the new crop. But with much less wheat drilled than usual, there isn’t going to be the tonnage, so dilution may well become an issue with this route, too.

The final, and highest risk option, is to hang on to the grain in the hope that as better quality crops become scarcer, buyers will relax their standards. However there is little chance of this while imported wheat with high hectolitre weights is available at competitive prices.

Simple steps to improve the value of low bushel weight grain

1. Run it through a recirculating batch dryer

2 Use a vacuum dust extractor or get the dryer out in the open on a windy day to blow away debris

3. Run for the first hour to bring sub-65kg/hl grain up two to three points. Every hour thereafter will have less effect

4. Use a cleaner/dresser where possible

5. Consider ‘over-yearing’ the crop to blend with next season’s grain

6. Talk to your merchant on a load-by-load basis.

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