Abstract: Leak detector systems for detecting leaks in sealed food packages are disclosed, as well as methods for detecting leaks in sealed food packages. The leak detector system includes advancing a food package to a seal testing station where a portion of the food package is deflected and a deflection characteristic is measured. If the deflection characteristic is greater than a predetermined deflection characteristic limit that a sealed package should undergo while being subjected to the predetermined force, indicating that the package contains leaks, the food package is rejected. Otherwise the food package is advanced from the seal testing station.