Foreign object and internal disorder detection in food materials using noncontact ultrasound imaging

A new noncontact air instability compensation ultrasound imaging technique was used for foreign object and defect detection in cheese and poultry. Air instability compensation transducers were used to obtain noncontact ultrasound images of boneless chicken breast with metal and glass fragments and cheese with holes, cracks, and foreign objects. The size of the glass and metal fragments used varied from 2 × 2 to 7 × 7 mm². Results demonstrated that the noncontact ultrasound imaging technique has a good potential for nondestructive and rapid detection of foreign objects and defects in food materials and could provide yet another alternative to conventional x-ray methods.