A growing body of scientific research supports what consumers already knew: ultraviolet light degrades the flavor of milk, and the translucent, high-density polyethylene (HDPE) jugs favored by dairy processors hastens the oxidation that causes flavor degradation. By adding white pigment to resin blenders to create opaque HDPE, dairies in the northeast (H.P. Hood) and southeast (Dean Food and Flav-O-Rich) have realized strong sales growth in recent years thanks to a better-tasting product.

Now Dean is bringing opaque milk containers to the Upper Midwest through the Land O' Lakes brand. "Because research shows that oxidation degrades milk's taste and its nutritional value, we developed FlavorTight packaging," says marketing chief Pat Graiziger of Dean Foods North Central Inc., Minneapolis. "The whole market is going to go white or some other color," adds another Dean official, despite increased production, handling and changeover costs.

Dean began rolling out half-gallon and gallon versions of the new Land O' Lakes jugs in August, supported by print ads in publications in the Dakotas, Minnesota, Wisconsin, Nebraska and Wyoming. The "Milk is better in the dark" tagline is complemented with the copy, "Keeps light out. Keeps nutrition and fresh taste in."

The packaging is being phased in at four former Land O' Lakes fluid milk plants in Minnesota and the Dakotas. Dean purchased the plants last year and formed a joint marketing partnership with the dairy cooperative.