Measuring and testing – Vibration – By mechanical waves
Utility Patent
2000-02-08
2001-01-02
Williams, Hezron (Department: 2856)
Measuring and testing
Vibration
By mechanical waves
C600S437000, C600S439000, C600S449000
Utility Patent
active
06167759
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to the field of ultrasonics. More specifically, the present invention discloses an ultrasonic system for grading meat.
2. Statement of the Problem
Objective measures of carcass and meat quality have been major objectives within the meat and livestock industry for many years. For example, current techniques implemented by the USDA to grade beef are based on assessment of “marbling”, the quantity and pattern of fat in the cut of meat. Such a grading system fails to accurately predict tenderness. In addition, the current USDA grading scheme seeks to correlate a high fat content with tenderness, which for a consumer viewpoint may discourage beef consumption. A cut of meat with a good tenderness rating and a moderate or even low fat content can provide the consumer with an attractive product.
Steaks that have low fat content and good (i.e., low) shear/tenderness values are known to exist, but cannot be identified non-destructively. They are only found after cooking and when graded by a taste panel. In contrast, the present technology is intended to perform non-destructive evaluation on live, fresh, or raw meat to identify those cuts of meat on a carcass, primal, cut meat, or a live animal that will be tender when cooked.
Various ultrasound-based technologies and other technologies have been investigated in the past for grading meat. The prior art in this field has used a range of parameters to grade meat, carcasses, or live animals, including:
(1) fat thickness (A-scan)
(2) rib-eye area, or other dimensional measurements (A and B-scan)
(3) marbling grade or percent fat
(4) subjective measurements of tenderness, palatability, or eating quality based on human taste panel assessments.
The ultrasonic propagation properties of meat, including attenuation, absorption, wave speed, and the non-linearity property, are largely associated with the molecular constituents and to a lesser degree, the high-level tissue structure. However, the tenderness of meat appears to be related primarily to the higher level structure—muscle fibers and fiber bundles, myofilaments, myofribil fasciculus, combined with connective tissue. When ultrasound waves scatter from the tissue structures, rather than propagate through, the backscattered signals appear to be due primarily to the various types and the hierarchy of the higher level structure. For example, reflections from muscle boundaries can be used to determine the edges of the rib-eye. Fat structures cause the speckle in B-scan ultrasound images that can be used for marbling evaluation. Using A-scan ultrasound measurements, the weak scattering from muscle fibers, groups of fibers, and connective tissue contribute to the back-scattered signals. These back-scattered signals can be analyzed to provide an indication of tenderness in subsequently cooked meat.
The prior art includes efforts to correlate ultrasound measurements with subjective properties of meat, such as tenderness, juiciness, palatability, and flavor intensity, as determined by human taste panels on subsequently cooked samples. However, “tenderness” is also subject to objective determination by measuring the shear force necessary to cut a meat sample. In particular, Warner-Bratzler shear (W-B shear or WBS) force values have long been used as the industry standard for an objective tenderness scale. It should be expressly understood that “tenderness” is used in this objective sense in this invention. In the present invention, ultrasound is used to grade tenderness for live, fresh, or raw meat and this is calibrated against the W-B shear values obtained for the subsequently cooked sample.
Although the ultrasound-based technologies disclosed in the prior art have been implemented at some farms and packing plants, there continues to be a long-existing, unmet need in the industry for an automated system to grade carcass and meat quality.
3. Solution to the Problem
The present system uses a novel combination of ultrasonic instrumentation and signal processing algorithms to analyze the back-scattered response signals and the total energy of the back-scattered signals from a meat sample in response to ultrasonic pulses. Experimental tests have demonstrated that this methodology produces an indicator that correlates well with local Warner-Bratzler shear force values for a wide variety of subsequently cooked meat samples.
SUMMARY OF THE INVENTION
This invention provides an ultrasonic system for grading meat by analyzing the integrated back-scattered signal. An ultrasonic transducer is placed in contact with the meat sample and a series of pulses are transmitted into the sample. The transducer receives the resulting back-scattered signals from the sample and produces an output voltage corresponding to the amplitude-time (depth) response of the back-scattered signals for the measurement volume which corresponds to the transducer beam-volume. The output voltage from the transducer is amplified and digitized (preferably to a resolution of at least 12 bits per sample) by an analog-to-digital converter. In some cases, various forms of signal conditioning or filtering are employed to improve signal characteristics. This data is then analyzed or stored for later processing. Gates are implemented in software executed by a computer processor to window and sample the data. A Hilbert Transform algorithm is used to determine the envelope function of the data. The envelope generally has the shape of a decaying exponential, i.e., y=exp(−Dt), where D is the log-decrement or attenuation factor for the back-scattered signal and t is time. The log-decrement/attenuation factor has been found to correlate with the local Warner-Bratzler shear for the meat sample. The attenuation factor can be determined by fitting an exponential curve to the envelope, or by converting the envelope function to a logarithmic scale and determining the slope of the resulting line. Additional features in the time-domain, rectified data and spectral domain can be used to refine the meat grading process and to give a “marbling” score. In particular, it may be possible to improve the accuracy of this approach by measuring the total back-scattered energy from the back-scattered signals and generating a grade for the meat based on a function of both the attenuation factor and the total back-scattered energy. Optionally, accuracy of the attenuation factor may be further enhanced by removing any anomalies in the back-scattered signal resulting from fat deposits in the meat.
In addition, the anomalies in the back-scattered signal resulting from fat deposits in the meat can be analyzed to determine to the “marbling” score.
These and other advantages, features, and objects of the present invention will be more readily understood in view of the following detailed description and the drawings.
REFERENCES:
patent: 4030343 (1977-06-01), Lund et al.
patent: 4099420 (1978-07-01), Stouffer et al.
patent: 4409838 (1983-10-01), Schomberg
patent: 4512195 (1985-04-01), Miwa et al.
patent: 4564019 (1986-01-01), Miwa
patent: 4655228 (1987-04-01), Shimura et al.
patent: 4785817 (1988-11-01), Stouffer
patent: 4830015 (1989-05-01), Okazaki
patent: 4941474 (1990-07-01), Pratt, Jr.
patent: 5048340 (1991-09-01), Thompson et al.
patent: 5079951 (1992-01-01), Raymond et al.
patent: 5303708 (1994-04-01), Stouffer
patent: 5316003 (1994-05-01), Stouffer
patent: 5339815 (1994-08-01), Liu et al.
patent: 5353796 (1994-10-01), Schroeder et al.
patent: 5398290 (1995-03-01), Brethour
patent: 5625147 (1997-04-01), Miles et al.
patent: 5685307 (1997-11-01), Holland et al.
patent: 0 337 661 A1 (1989-10-01), None
patent: 0 523 865 A1 (1993-01-01), None
patent: 0 523 865 B1 (1993-01-01), None
patent: 2 289 763 (1996-11-01), None
patent: WO 94/10562 (1994-05-01), None
patent: WO 94/25857 (1994-11-01), None
patent: WO 94/25867 (1994-11-01), None
patent: WO 97/27755 (1997-08-01), None
Bond Leonard John
Kishoni Doron
Mahrer Kenneth David
Colorado Seminary
Dorr, Carson , Sloan & Birney, P.C.
Miller Rose M.
Williams Hezron
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