The use of elastography to measure quality characteristics of pork semimembranosus muscle

• Published in: Meat science Vol. 53; no. 1; pp. 31 - 35
• Main Authors: Berg, Eric P., Kallel, Faouzi, Hussain, Fasahat, Miller, Rhonda K., Ophir, Jonathan, Kehtarnavaz, Nasser
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.09.1999; Elsevier
• Subjects: Biological and medical sciences; color; drip loss; Elastography; fat; Food industries; Fundamental and applied biological sciences. Psychology; ham; image analysis; intramuscular fat; Meat and meat product industries; meat quality; Pork quality; shear; skeletal muscle; strain; texture; Texture parameter; toughness; ultrasonic devices; ultrasonic strain image analysis; ultrasonics; ultrasonography; Ultrasound; water holding capacity; Texture parameter; Pork quality; Ultrasound; Elastography; Compression; Grease; Meat product; Shear force; Texture; Semimembranous muscle; Image analysis; Ultrasonic imaging; Quality; Tenderness; pH; Elastic properties; Pork
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/S0309-1740(99)00033-9

The objectives of this study were to determine if ultrasonic strain image analysis could estimate pork eating quality parameters (such as fresh color, drip loss, and Warner/Bratzler shear). Intact semimembranosus (SM) muscles (cap off) were analyzed for ultimate pH (pH ult). Forty-five SM muscles were selected from the larger allotment of fresh hams over a 3-week period. The SM muscles were selected based on high and low pH ult in an attempt to represent a wide range of pork quality. Ultrasonic strain images were obtained perpendicular to the SM muscle fibers of an 8-cm cube. Radio-frequency data from each SM were obtained from a field-of-view (FOV) of 40×30 mm 2 and digitized for each compression step. Tissue displacements were computed for each compression step. Tissue strains were computed from displacement data located in the FOV representing areas of harder and softer muscle tissue and converted to gray scale images at 256 levels. Tissue irregularity of hardness and softness was measured using Fractal dimension and Haralicks parameters. Twenty-one Fractal dimension (FR) parameters, at two neighborhood distances ( N), from each strain image and nine Haralick's (HAR) textural parameters (inter-pixel distance=1) were analyzed for each image. The variable FR4 N4 had a −0.279 correlation with SM ultimate pH ( p<0.10); FR6 N8 correlated to WB shear force at 0.325 ( p<0.05); and FR21 N8 had a correlation coefficient of 0.364 with intramuscular fat ( p<0.01). Linear regression equations generated from FR N and HAR parameters for intramuscular fat ( R 2 =0.468), Warner/Bratzler shear ( R 2 =0.360), and 30 h drip loss ( R 2 =0.208). Although elastographic measurement was significantly correlated to shear ( p<0.05), a better understanding of physical meat texture is necessary before elastography can be used to identify superior quality pork.