Use of air-coupled ultrasound for the non-invasive characterization of the textural properties of pork burger patties

Abstract

[EN] This study tests the feasibility of air-coupled ultrasound for the characterization of the textural properties of pork burger patties. The samples were prepared by mixing lard at different percentages (0, 20, 40, 60 and 80%) with a commercial burger meat mixture. Through-transmission airborne ultrasound measurements (250 kHz) were carried out at 5 and 20 degrees C. Ultrasonic velocity at 5 degrees C increased exponentially with fat content (r = 0.99), varying from 1587 to 1668 m/s, whereas it remained fairly constant at 20 degrees C (1644 to 1624 m/s). Ultrasonic attenuation decreased with fat content following an exponential pattern (r = 0.83 at 5 degrees C; r = 0.93 at 20 degrees C) and ranged from 62.6 to 44.8 Np/m at 5 degrees C, and from 76.7 to 42.2 Np/m at 20 degrees C. Noticeable correlations were found between hardness and ultrasonic velocity (r = 0.89 at 5 degrees C), and between Total Relaxation Capacity and ultrasonic attenuation (r = 0.89 at 5 degrees C; r = 0.99 at 20 degrees C). Additionally, airborne ultrasound allowed an accurate (mean relative difference 2.3%) prediction of burger thickness.