Reflection or Refraction: It is possible that the flash of light was caused by a reflection or refraction of light from an external source. This could occur if there was a passing car or other source of light that momentarily entered the store room and reflected off a surface, creating a flash of light.

Electrical Issues: Another possibility is that the flash of light was caused by an electrical issue within your home. This could be a result of a short circuit or a malfunctioning electrical device, which could produce a sudden burst of light.

Spirit Presence: Some people believe that flashes of light or orbs can be associated with the presence of spirits or other paranormal entities. These lights are often referred to as orbs and are believed to be manifestations of spiritual energy. According to this belief, the flash of light you witnessed could be a sign of a spiritual presence in the store room.

Communication Attempt: In paranormal circles, flashes of light are sometimes interpreted as attempts by spirits to communicate with the living. It is believed that spirits can manipulate energy to create these flashes as a way of getting attention or conveying a message.