Ultrasonic and acoustic investigation of cheese matrix at the beginning and the end of ripening period

In this paper, a low frequency, dry contact, ultrasonic technique devoted to the study and characterization of cheeses at the beginning and the end of ripening period is investigated. For compact or weakly opened matrix found in the early step of cheese making, ultrasonic velocity is indicated to represent the viscoelastic properties of the matrix. But, limitations occur in the use of ultrasound especially for mature cheeses which present very high degrees of opening. As ultrasound becomes no longer usable, a tap-test acoustic technique has been developed and employed for cheese classification. A good correlation between ultrasonic data and tap-test data is shown.