NFU Scotland commissions farm pot ale syrup handling study

21 October 2013

Glasgow Caledonian University (GCU) has been commissioned by the National Farmers Union of Scotland (NFU Scotland) to investigate and make recommendations for the improved handling of pot ale syrup, a co-product of whisky distillation used by farms as animal feed. 

Funded by an SFC Innovation Voucher, which encourage organisations to develop innovative products, processes and services and explore new markets, the feasibility study aimed to establish methods for the improved handling of pot ale syrup on farms.

The GCU project comprised a site visit, a literature survey of the current literature on the subject and a report bringing together the key conclusions of the work.

GCU researchers made separate visits to the various stakeholders in the handling process, from the whisky distillers to the intermediate handlers, the feed merchants, and finally to a number of different sized farms.  It was discovered that the distillers were confident and proficient in the handling of the pot ale syrup, largely due to the process controls in place, and the fact that it was not held on site for extended periods of time. 

Feed merchants, who occasionally deal with smaller storage containers, found that settling of the solids can cause a blockage in the outlet of these smaller containers, which is approximately quarter of the size of those on a large storage tank. This led to a recommendation that equipment could be used to agitate the contents of these containers and potentially put the solids back in suspension.

The study found that smaller farms may be supplied their pot ale syrup by a range of sources, increasing the potential for differences between batches.  This observation lead to another key recommendation from the feasibility study; that being a better understanding of the flow properties of the pot ale syrup and the variability of these with product composition and source.

The mixing of the pot ale syrup with other feed constituents, such as barley or silage, was also a point of variation between the different sizes of farms.  The larger farms tended to use a mixer wagon, while small farmers tend to mix on barn floors.  It was therefore recommended that an investigation be undertaken into an appropriate mixing device for these farmers that satisfied their requirements for mixing quality and total cost, including the equipment cost and on-going running costs. 

In conclusion, provided the pot ale syrup is produced to a consistent standard and is not left in storage for a lengthy period, the handling should not present significant difficulties.  To assist the farmers in using the pot ale syrup it is recommended that a better understanding of the properties and their variability is obtained, increasing the likelihood of better handling and, ultimately, mixing as well.