A method of collecting expressed breast milk for later feeding to an infant includes providing a spout pouch, coupling the spout of the spout pouch to a breast pump, and operating the breast pump to express breast milk into the spout pouch, so that the spout pouch collects the expressed breast milk. A method of feeding a liquid to an infant includes providing the liquid in a spout pouch, and coupling a nipple to the spout of the spout pouch. A nipple for such use includes a connector having an axial bore that is coupled to an orifice in the nipple and the connector forms a liquid tight seal with the spout of the spout pouch. Other systems, methods, and components are also provided.
