Arizona Hydroponic Farming LLC of Eloy, Arizona, has voluntarily recalled its ''4oz Alfalfa Sprout Cup'' as a preventive measure because of a positive test result in California for Salmonella. The potential for contamination was noted after routine testing by the USDA revealed the presence of Salmonella in some 4 ounce packages collected from a customer in California. The affected AZ Hydroponic Farming shipments are questionable since they were grown from the same batch of seeds as the sprouts sent to California.