More and more cereal farmers are reporting issues with malting barley rejections due to an increase in the presence of skinned grains over the past two harvests.

Research shows that skinned grains or skinning is caused by a loss of the husk during or post-harvest and it is said to have very serious consequences for the malting process.

According to Teagasc’s Dermot Forristal, skinning of malting barley grains is a physiological issue and it is particularly influenced by season.

The cut-off level for skinned grain inclusion varies by malting barley buyer, he said, with the cut-off currently sitting between 1-6%.

Altering the threshing settings of the combine

Speaking to Agriland, the Teagasc Principal Research Officer said that altering the threshing settings on the combine may help reduce the problem with skinning and allow grains to be accepted for malting.

“It doesn’t solve the problem, but it might help,” he said.

Forristal said that farmers should set the combines threshing settings as low as possible to allow for the separation of the grain from the chaff.

He advised farmers not to apply any extra pressure, as this could cause potential damage or skinning to the cereal grain and force the load to be rejected.

The threshing settings will vary from combine-to-combine, he said, but it is important that farmers thresh the malting crops as gently as possible to separate the grain without causing damage.

To reduce the threshing pressure, he said, farmers can adjust the drum speed or the concave opening up to the point that the grain is separated from the chaff.

He also said that some combines, such as Claas and New Holland models, are fitted with separation units which can adjusted to reduce the pressure applied during the threshing process.

Avoid letting malting barley crops get to ripe

Forristal also said that skinned barley grains may occur due to wetting and drying and he advised farmers not to let their crops get over ripe, as this can lead to an increase in skinned grains.

“It is much easier to thresh a very ripe grain crop.

“The temptation is to let crops get over ripe, but as the crop gets riper the husk becomes easier to detach,” he said.