The campaign to replace French maize with Scottish wheat for the production of grain spirit has hit a setback due to quality issues.
Farmers Guardian understands a large scale trial at North British Distillery in West Lothian concluded the spirit yield per tonne in home produced wheat was too variable.
Fife Farmer and agronomist Gordon Rennie has been at the forefront of the ’In The Spirit’ campaign which seeks to persuade distillers that if a bottle of Scotch Whisky is labelled ’Produce of Scotland’ as many as possible of the ingredients should be home produced.
The water used in the process is invariably Scottish as is most of the malted barley.
Imports are generally only used in times of shortfall.
However, at least two of the giant distillers have been using imported maize as a feedstock to bulk up the blends, rather than wheat.
Following the Brexit related devaluation of sterling, wheat looked more attractive and North British Distillery, which uses 160,000 tonnes per year of French maize, began a large scale trial but reports suggested this had been suspended in the meantime.
Maize consistently produces 480 litres per tonne of spirit but the wheat that has replaced it is producing between 440 litres and 460 litres per tonne.
A lower spirit yield is expected from wheat and is compensated for in price but the inconsistency of the Scottish grain reportedly causes problems in managing the process.
Mr Rennie said: “The only way to solve this is for the farming community to step up to the plate and produce the right product using the correct varieties.
"Wheat will need to be capable of being tested in bulk stores before delivery to show that it is capable of producing 460 litres per tonne.
“The only way forward is to follow the example of the oat growers with the Oatco co-operative and organise deliveries of suitable varieties such as Leeds and Istabraq. I am frustrated that at SRUC and AHDB meetings suitability for distilling is never mentioned.
“Scottish growers are the only people in the world who can grow high spirit yielding wheat. It is our opportunity to produce a premium wheat and we should not miss it."