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HMRC internal manual

VAT Food

Items benefiting from the relief: products used for animal feed and other purposes: silage enhancers

Silage enhancers are products, usually derived from molasses or other sugars, which are added to silage to increase fermentation and absorb and retain the liquid effluent which would otherwise escape during the process and be lost. Since silage effluent contains valuable nutrients, this effluent retention increases the nutritional quality of the silage produced. It also prevents effluent run-off from contaminating nearby river water. Many silage enhancers contain live silage bacteria, which contribute directly to the rate of fermentation. Non-bacterial products serve primarily to retain effluent.

Most silage enhancers, including all bacterial products, are not classed as feeding stuffs for VAT purposes, as they are not themselves fed to the animal, either straight or as an ingredient in a feed. However, many non-bacterial silage products are composed of ingredients which would be considered animal feed in their own right, and are held out as having alternative uses as a direct feed.

The liability of silage products depends on their primary use, and whether they can be fed direct to animals or not. Products used exclusively for adding to silage before or during fermentation, and which are not fed direct to animals, are standard-rated; non-bacterial products which are marketed as having an alternative direct-feed use may be zero-rated. You should be able to determine which category a product falls into from the accompanying marketing literature.