Browsing by Author "Belk, Keith Evan, 1961-, advisor"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Open Access Instrument evaluation of lamb carcass yield and quality characteristics(Colorado State University. Libraries, 2011) de Carvalho Neto, Filogomes Alves, author; Belk, Keith Evan, 1961-, advisor; Tatum, J. Daryl, committee member; Woerner, Dale R., committee member; Pendell, Dustin L., committee memberTo view the abstract, please see the full text of the document.Item Open Access Nutrient analysis of the beef alternative merchandising cuts(Colorado State University. Libraries, 2011) Desimone, Tonina Leslie, author; Belk, Keith Evan, 1961-, advisor; Engle, Terry E., committee member; Woerner, Dale R., committee member; Kendall, Patricia A. (Patricia Ann), 1947-, committee memberSix carcasses were selected from each of four different beef packing plants. Carcasses were a combination of USDA Yield Grade 2 (n = 12) and USDA Yield Grade 3 (n = 12), US Quality Grade Premium Choice (n = 8), Low Choice (n = 8), and Select (n = 8), and two genders (steer n = 16, heifer n = 8). The four beef packing plants were located in the Midwestern part of the United States: two in Colorado, one in Kansas, and one in Nebraska. Beef Ribeye, Beef Loin, Strip Loin, and Beef Loin, Top Sirloin Butt subprimals were collected from both sides of these carcasses. Subprimals were vacuum packaged and aged for 14 to 21 days at 0 to 4°C. Subprimals were fabricated into the Beef Alternative Merchandising (BAM) cuts, as described by the Beef Innovations Group of the National Cattlemen's Beef Association (NCBA), at Colorado State University Meat Laboratory. Cuts from both sides of the carcass were randomly designated for use in obtaining cooked and raw nutrient data. All cuts were vacuum packaged and stored at -18°C for subsequent cooking and/or dissection. Raw cuts were thawed at 0 to 4°C for 24 to 48 h and then dissected into separable lean, separable fat, and refuse (connective tissue). Cuts to be cooked were thawed for 24 to 48 h at 0 to 4°C, roasted or grilled, tempered for 24 to 48 h at 0 to 4°C, then dissected into separable lean, separable fat, and refuse. Following dissection, both raw and cooked samples were homogenized and then stored at -80°C for subsequent nutrient analysis. The BAM cuts were analyzed for moisture, crude protein, percent lipid, and ash. Of the muscles that comprise the BAM cuts, the Spinalis dorsi contained the highest percent fat and lowest percent moisture. As fat content increased, moisture content subsequently decreased. The muscles from the Top Sirloin Butt were the leanest of the muscles comprising the BAM cuts. Fatty acid composition and cholesterol content was determined using gas liquid chromatography. Of the fatty acids identified, saturated-, monounsaturated-, and polyunsaturated fatty acids represented 44.92, 46.04, and 3.04%, respectively. The Gluteus medius contained the highest percentage of polyunsaturated fats regardless of Quality Grade. Of the fatty acids detected, oleic, palmitic, and stearic acids represented 74.56% of the fatty acid profile of all BAM cuts. Trans fats totaled 6.4% of the fatty acids identified for all the BAM cuts. This study identified seven cuts from three Quality Grades that qualify for USDA Lean and one cut from two Quality Grades that qualify for USDA Extra Lean.Item Open Access Prediction of meat tenderness using high resolution imaging(Colorado State University. Libraries, 2010) Howard, Scott Thomas, author; Belk, Keith Evan, 1961-, advisor; Tatum, J. Daryl, committee member; Chapman, Phillip L., committee memberTenderness plays an important role in the sensory attributes of beef products. The objective of this study was to obtain the highest quality and resolution images of cross-sections of beef Longissimus dorsi surfaces that could likely be replicated in a commercial environment; and, to develop algorithms and regression equations that predict aged beef shear force. Fifty carcasses were identified at each of three commercial beef processing facilities in Colorado, Nebraska and Texas (total N = 150). A-maturity carcasses were selected to fill an equal distribution over the entire range of beef marbling scores; 1/3 of carcasses represented marbling scores from Practically Devoid 00 to Slight 40, 1/3 from Slight 50 to Small 90 and 1/3 from Modest 00 or higher. Carcasses derived from cattle supplemented with Zilpaterol hydrochloride (n = 25, based on harvest facility records) were identified as such. Samples were excised from the Longissimus muscle immediately posterior to the 12 th /13 th rib interface and imaged using the Tenera Technology High Resolution Imaging System; in addition, reflectance measurements (L*, a*, b*) were obtained. Samples were aged for either 7 or 14 days prior to freezing. Steaks were fabricated from frozen samples for Warner-Bratzler shear force (WBSF) determination. Images were analyzed using the custom developed Tenera Technology ZARMT software program, generating 10 output variables (diaSml, propSml, diaLrg, propLrg, ratDia, ratProp, medDia, medProp, diaNormMax and propNormMax) thought to represent ultra-structural characteristics of muscle such as fiber diameter, proportion of large versus small fibers and predominant size of muscle fiber within a given sample, which have previously been associated with beef tenderness (Hiner et al., 1953; Tuma et al., 1962; Herring et al., 1965; Cooper et al., 1968). In 14d aged steaks from harvest facility one, the use of high resolution variables explained an additional 11% of the variation in WBSF value over the use of marbling and color variables alone. Within harvest facility two and three, high resolution variables allowed for explanation of an additional 25% and 17% of the variation in 14d WBSF respectively. For samples aged 7d, high resolution variables allowed for explanation of an additional 8%, 14% and 34% of the variation in WBSF values of steaks from harvest facility one, two and three respectively. Fourteen days postmortem, inclusion of high resolution variables improved classification of "tender" steaks (WBSF less than or equal to 3.7, Platter et al., 2003a) 40%, -3% and 7% from harvest facility one, two and three respectively. Classification of "tough" steaks (WBSF greater than 3.7, Platter et al., 2003a) within steaks aged 14d was improved by -10%, 0% and 0% through use of high resolution variables. In classification of "tough" versus "tender" steaks 7d postmortem, equations containing high resolution variables correctly classified an additional 6%, 14.3% and 7.1% of "tender" steaks and 0%, -5.9% and 9.1% of "tough" steaks from harvest facility one, two and three respectively. Compared with the use of marbling and reflectance measurements alone, the use of high resolution variables improved the ability to explain WBSF at 7d and 14d, as well as in the designation of "tough" and "tender" steaks/carcasses, suggesting this technology, or one measuring similar traits could improve the assurance of tender beef products at the consumer level.Item Open Access Prediction of primal and subprimal beef yields with video image analysis(Colorado State University. Libraries, 2011) Nunes, Trevor Francis, author; Belk, Keith Evan, 1961-, advisor; Tatum, J. Daryl, committee member; Smith, Gary C., committee member; Chapman, Phillip L., committee memberAn ability to segregate carcasses based on both primal and subprimal yields would further facilitate value-based marketing in the beef industry. This study was conducted to evaluate Video Image Analysis (VIA) output to predict fabricated primal and subprimal yields. Carcasses were selected based on yield grade (YG 1, YG 2, YG 3, YG 4, and YG 5) as well as hot carcass weight (< 341 kg and ≥ 341 kg). A yield dissection was performed and at each step in fabrication, recovered product weights for each carcass to remain in the study summed to ≥ 99 % of the starting chilled weight of each primal and subprimal. For yield predictions, VIA output from 12th/13th rib interface images from the VBG 2000 (single-component; n = 142, development; n = 58, validation), or from VBG 2000 output in combination with output from loin/round primal interface images from the VPS 2000 (dual-component; n = 129, development; n = 56, validation) were regressed on yields of fabricated primals and subprimals. Yield variables were predicted as a percent of the aggregate chilled carcass side weight. Results from prediction equations for primals or the largest subprimal representing a primal in the study, indicated moderate and low predictive capability for development and validation datasets, respectively. For the square cut chuck (IMPS 113), commodity iii trimmed brisket (IMPS120, PS0 1), ribeye (IMPS 112A, PSO 3, 5.1 cm x 5.1 cm lip-on), short plate (IMPS 121), loin primal (IMPS 172), flank primal, and round primal (IMPS 158) R2 / adjusted R2 values (development / validation) of 0.39 / 0.11, 0.16 / 0.05, 0.31 / 0.12, 0.40 / 0.03, 0.56 / 0.12, 0.35 / -.005, and 0.64 / -0.05, respectively, for single-component predictions and 0.60 / -0.13, 0.57 / -0.03, 0.40 / 0.08, 0.52 / -0.15, 0.66 / -3.42, 0.66 / -3.42, 0.47 / -0.004, and 0.73 / -0.10, respectively, for dual-component predictions was observed. The best performing single-component model was for the tenderloin (IMPS 189A) with R2 / adjusted R2 values (development / validation) of 0.42 / 0.50. The best performing dual component model was for the cap off inside round (IMPS 169A) with R2 values (development / validation) of 0.58 / 0.30. The ability of single-component and dual-component equations to predict yields of several primal and subprimal cuts, with reasonable accuracy and precision in the development dataset, yet low accuracy and precision in the validation dataset, suggests that the VIA systems tested in this study do not have the potential as tool for more sensitive carcass segregation at this time. Further investigation to reveal the full potential of dual-component primal and subprimal cut yield prediction, perhaps looking at a sample population with greater variance (i.e., equal number of yield grades for equation development) and having VPS 2000 images available from each primal surface to provide independent variables representative of the entire carcass, is justifiable.