The present invention involves the discovery that various liquid (whey) streams drained or expelled from cheese curd after salt addition in the preparation of cheese contain enriched levels of bioactive proteins such as lactoferrin, lactoperoxidase, immunoglobulins, and growth factors. According to the invention, these proteins may be further enriched through manipulation of the cheese salting process as described herein. The methods of the invention may be used to produce various whey products with enriched levels of all the above bioactive proteins present and, through manipulation of salting conditions, to enrich these proteins selectively.
