Baby food pouch bags are made of plastic and a range of other materials. StandUpPouches.net laminates together several layers of plastic and other materials to make custom printed stand up pouches. These pouches are designed to be puncture resistant. They can bear a lot of pressure, so they are unlikely to explode in checked luggage.
Food pouches containing gas (as in potato chips) or easily vaporized liquids (carbonated drinks) expand when outer pressure declines. Air pressure decreases when an airplane rises up. If the walls of a baby food pouch are not strong to bear this pressure, it will explode. It is worth noting here that solid foods (beef jerky) do not require as strong packaging as foods with liquid and gaseous content do. It happens because expansion is negligible in the case of solid foods, so the effect of increase pressure is minimal.
To conclude, strong pouches containing solid foods will not explode in checked luggage, but weak pouches with liquid or gas content will certainly do.