A baby bottle includes a container having a feeding end and an air inlet end opposite the feeding end, a nipple releasably coupled to the feeding end, and a valve releasably coupled to the air inlet end. The valve includes a body extending into the container when the valve engages the air inlet end of the container, and a membrane recessed relative to the body. The membrane includes a slit, which is configured to open in response to a negative pressure within the container and resiliently close in absence of the negative pressure.
