Enables UDP-galactose:glucosylceramide beta-1,4-galactosyltransferase activity. Involved in glycosphingolipid biosynthetic process. Predicted to be located in Golgi cisterna membrane. Predicted to be integral component of membrane. Predicted to be active in Golgi apparatus. Orthologous to human B4GALT6 (beta-1,4-galactosyltransferase 6). [provided by Alliance of Genome Resources, Apr 2022]