Certain malts cause premature flocculation of yeast in brewery fermentations. Initial results suggested that the isolated husk factor(s) putatively responsible for premature flocculation bind to yeast cell walls. Because barley contains lectins, and lectins by definition bind specific sugars, it is probable that, if present in adequate concentrations, they would be instrumental in producing premature flocculation by binding to yeast cell walls. In the first part of this work, a barley lectin was isolated by affinity chromatography and shown to survive the malting and brewing process, but the purified lectin was not found to be implicated in premature flocculation. In the second part of this study, we used yeast that had undergone premature flocculation as a form of affinity chromatography column to isolate the factor(s) in malt husk responsible for premature flocculation. Glucose, mannose,α-methylmannoside, andN-acetylglucosamine were able to release factor(s) from prematurely flocculated yeast. This factor(s) caused early flocculation when added back to normal fermentations. Premature flocculation could be prevented by preincubating the flocculation factor(s) from malt husk with the above sugars. Lactose, however, was unable to release any flocculation factors from the yeast and was also unable to prevent early flocculation when incubated with the malt husk factor. The malt husk factor has lectin-like sugar specificities. Further corroborative work is underway.