Scotch grain distillers' solubles, known commercially as ‘Scotaferm’, are now available in Great Britain, and feeding trials were made to investigate the value of this material in the diet of the dairy cow. The solubles are a free-flowing light-brown powder produced by evaporating and then spray-drying the liquor (‘spent wash’) remaining in the whisky still after distilling the spirit. The analysis of a typical sample is 5% moisture, 29% protein (20% digestible protein as estimated by pepsin digestion), 9% fat, 5% crude fibre, 11% ash and 41% nitrogen-free extract. The food is a good source of B-vitamins and contains 3·8% calcium.