Yes, you can bring powdered milk on a plane, but it is subject to specific security screening procedures. According to TSA and international security guidelines, powder-like substances (including powdered milk, baby formula, and protein powder) in carry-on bags are generally limited to quantities of 12 ounces (350 ml) or less. If you have more than this amount, it must be removed from your bag and placed in a separate bin for X-ray screening. For parents traveling with infants or toddlers, powdered milk and baby formula are considered medically necessary liquids/powders, meaning you are allowed to bring larger quantities than the standard 3.4-ounce limit. However, you must inform the security officer at the start of the screening process. They may perform additional testing on the powder, such as an explosive trace detection swab. To make the process smoother, it is recommended to keep the powder in its original, labeled container and ensure it is easily accessible in your bag. While not strictly required, using clear or translucent containers can also help the officers verify the contents more quickly.