Browsing by Author "Tatum, J. Daryl, committee member"

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Open Access
A proof of concept to differentiate among differences in flavor of American lamb using volatile flavor compound analysis
(Colorado State University. Libraries, 2023) Isaacs, Karissa Ann, author; Woerner, Dale R., advisor; Belk, Keith E., advisor; Tatum, J. Daryl, committee member; LeValley, Stephen B., committee member; Heuberger, Adam L, committee member; Meiman, Paul, committee member
Experiments were conducted on lamb legs (n=25 per treatment) from 3 dentition groups [ young lambs (0 permanent incisors), yearlings (2 permanent incisors) and mature sheep or mutton (>2 permanent incisors)] to establish a proof of concept for differentiating the inherent differences in flavor that exist in meat from ovine animals of various age classes using volatile flavor compound analysis. The legs were selected from commercial processing facilities. Differences among age group, breed type, sex and production background were evaluated for sensory analysis and volatile compound analysis. Trained panelists evaluated ground meat patties from each leg for lamb flavor intensity and off flavor intensity. In addition, samples were analyzed to determine percentages of lipid, moisture, protein, and ash as well as to identify volatiles produced during cooking of a raw composite of lean and fat from the external surface of the leg. Analysis of variance was conducted for sensory flavor attributes relative to animal age and production background (grain vs grass) helped to describe the experimental samples. Ratings for lamb flavor intensity were higher (P < 0.05) for lamb carcass samples than for yearling carcass samples, and lamb flavor intensity scores were similar for lamb and mature age classes. Off-flavor intensity ratings were highest (P < 0.05) for samples from mature lamb carcasses, while lamb and yearling samples produced the lowest (P < 0.05) off-flavor intensity ratings. Lamb flavor intensity and off-flavor intensity ratings were higher (P < 0.05) for grass-fed lamb samples compared to grain-fed lamb samples. Mature samples had the greatest (P < 0.05) off-flavor intensity, while lamb and yearling samples had the least (P < 0.05) off-flavor intensity. Grass-fed lamb samples had the higher (P < 0.05) lamb flavor intensity scores and higher (P < 0.05) off-flavor intensity scores. Correlations between sensory attributes and metabolites helped to narrow the 500+ to 50 of significance. Findings indicated that metabolites (volatile compounds) were related to flavor of sheep meat. Finally, regression techniques helped to predict lamb flavor intensity, off flavor intensity and proof-of-concept for classifying lamb flavor.
Open Access
An evaluation of the effectiveness of FreshCase® technology to extend the shelf life of beef and pork
(Colorado State University. Libraries, 2012) Yang, Xiang, author; Belk, Keith E., advisor; Woerner, Dale R., advisor; Chapman, Phillip L., committee member; Tatum, J. Daryl, committee member
This research evaluated the effect of FreshCase®, a novel packaging technology that has been shown to extend the shelf life of whole muscle beef and ground beef, whole muscle pork and ground pork sausages by stabilizing fresh meat color. FreshCase® utilizes a high-barrier nitrite containing film in conjunction with vacuum packaging technology. Storage life was defined by the number of days required to reach an aerobic psychrotrophic plate count of 107 log CFU/g, and all treatmes were stored and evaluated until storage life expired. The storage life for beef steaks stored in FreshCase® packages at 4°C was 36 days; and the shelf life for ground beef stored in FreshCase® packages at 4°C was 12 days. The shelf life for pork chops stored in FreshCase® packages at 1°C was 46 days; and the shelf life for ground pork sausages stored in FreshCase® packages at 1°C was 19 days. Values for CIE a* (redness) were greater (P < 0.05) for FreshCase®-packaged samples for both beef steaks and ground beef with the increase of storage time. Both pork chops and sausages stored in FreshCase® packages retained more acceptable redder color (P < 0.05) than those stored in Control packages throughout storage. By the point at which spoilage was detected, off-odors of putrid, acid, sour and rancidity for FreshCase®-packaged samples were detected, but were present at very low level. Likewise, by the point of spoilage, no significant differences (P > 0.05) were found between samples in control and FreshCase® packages in all off-odors detection for both pork chops and sausages and the intensities of these off-odors were very low. Also, beef and pork samples resulted in very low (1.19 mg malonaldehyde/kg and 0.55 mg malonaldehyde/kg, respectively) TBA values throughout storage. Therefore, utilization of FreshCase® Technology in whole muscle beef and ground beef, whole muscle pork and ground pork sausages results in a more stable fresh red meat color with a low level of off-odors, and lipid oxidation. FreshCase® did not influence microbial growth in vacuum packaged samples.
Open Access
Beef tenderness and management of calf-fed Holstein steers to meet market standards
(Colorado State University. Libraries, 2013) Howard, Scott Thomas, author; Belk, Keith E., advisor; Woerner, Dale R., committee member; Tatum, J. Daryl, committee member; Scanga, John A., committee member; Salman, M. D., committee member
Tenderness is one of the most influential sensory attributes determining consumer acceptance of beef products. Beef at retail represents production of a diverse cattle population, including both beef breeds and cattle bred for milk production. Objectives of this work were to first benchmark tenderness at the retail level and then determine appropriate management strategies to maximize quality and yield of calf-fed Holstein steers. Fifty-four stores in thirty U.S. cities were sampled from June 2011 through May 2012 to benchmark tenderness of beef steaks at retail as assessed by Warner-Bratzler shear force (WBSF).Top loin (N = 980) and sirloin (N = 860) steaks were purchased and shipped via overnight delivery to Colorado State University, Fort Collins, CO. The survey was divided into two periods based on samples shipped fresh and frozen on arrival (Period 1) or samples shipped frozen and stored frozen (Period 2). Mean WBSF values during Period 1 were 2.9 and 3.9 kg for top loin and sirloin steaks, respectively. Frequencies of steaks classified as tough (WBSF ≥ 4.4 kg) were 8.6% and 17.7% for top loin and sirloin steaks, respectively. Examination of coefficients of variation associated with means reflecting the influence of freezing, retail display and shipping suggested that variance remained unchanged (± 2.0%) with respect to shear force values; however, mean shear force values were reduced as a result of shipping conditions. Mean WBSF values during Period 2 were 3.4 and 4.0 kg for top loin and sirloin samples, respectively. Frequencies of steaks classified as tough were 14.3% and 24.8% for top loin and sirloin steaks, respectively. Calf-fed dairy steers comprise approximately 10% of fed-beef harvested in the United States, annually (Moore et al., 2012).This population of cattle is much different genetically and requires use of growth promotants to meet comparable feedlot performance to that of beef breeds. The effect of beta-agonist supplementation on live performance, carcass characteristics, fabrication yields and beef quality of calf-fed Holstein steers was investigated using steers implanted with a combination trenbolone acetate/estradiol based implant and blocked by initial weight into pens (N = 32). Pens consisted of 90 steers each and were randomly assigned to one of four management strategies including: implant only, ractopamine hydrochloride (RH) fed at 300 mg/hd/d for the final 30 d of finishing or RH fed at 400 mg/hd/d for the final 30 d of finishing, and zilpaterol hydrochloride fed at 6.8 g/ton for 23 d with a 3 d withdrawal prior to harvest. Feed efficiency was improved in beta-agonist fed steers 18 to 25% and hot carcass weight was increased by 1.8 to 3.7% (P < 0.05). Beta-agonists increased saleable yield by 0.6 to 1.9%, decreased fat by 0.6 to 1.3% and shifted tissue distribution such that a greater percentage of side weight was comprised of the muscles of the round (P < 0.05). Changes in development were observed as a result of beta-agonist use, specifically as an increased proportion of weight comprised of muscles of the hindquarter (P < 0.05). Use of beta-agonists negatively impacted shear force and sensory attributes. Beta-agonists had no effect on marbling; however, supplementation using any treatment increased shear force by 9 to 26%. Zilpaterol hydrochloride reduced trained panel ratings for tenderness, juiciness and flavor, but this was not observed in beef from steers treated with RH at 300 mg/hd/d. These effects were nearly linear as dose and potency of beta-agonists increased. The most aggressive beta-agonist treatments increased incidence of samples failing to be certified as tender from just over 10% in controls to approximately 20 to 25% at 21 d postmortem (P < 0.05). To produce beef comparable to current tenderness levels at retail, producers must appropriately manage use of beta-agonists and implants in populations of calf-fed Holstein steers.
Open Access
Discovering consumer preferences for steak thickness and common food service cookery methods for beef strip loin steaks
(Colorado State University. Libraries, 2016) Shubert, Danielle Marie, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Tatum, J. Daryl, committee member; Delmore, Robert J., committee member; Hess, Ann, committee member
The objective of this study was to quantify consumer preferences for steak thickness and cookery method. Paired strip loins from 38 carcasses with Small marbling scores were obtained from a commercial packing facility. Each strip loin was cut into 2 sections (4 sections per carcass) and each section was randomly assigned to 1 of 4 cookery methods (COOK): 1) grill (GRILL); 2) grill mark then finish in a steam oven (MARK+FINISH); 3) par cook in a steam oven then mark on a grill (PAR+MARK); 4) broil (BROIL). Each section was vacuum-sealed and aged at 2oC for 21 days before being frozen. After freezing, three sets of paired steaks were cut from each section representing three steak thickness treatments (THICK): 1) 1.9-cm; 2) 2.5-cm; 3) 3.8-cm. For each cookery method and steak thickness combination pair, a single steak was designated for evaluation by a consumer panel while the other steak was assigned to objective testing for measures of tenderness, cook loss, and visual appearance. Known beef consumers (N = 307) evaluated each of the 12 treatment combinations of thickness and cookery method for tenderness, juiciness, flavor desirability and overall desirability using a 15-cm unstructured line scale. A significant COOK x THICK interaction (P < 0.05) affected consumer panel ratings for tenderness, juiciness, and overall desirability. As a main effect, COOK influenced (P = 0.0005) consumer ratings for flavor desirability; however, inconsistencies between the present and previous studies suggest that consumer-rated flavor desirability may have been affected more heavily by tenderness, and juiciness in what is termed a “halo effect” than by actual differences in flavor due to cookery method. The BROIL, 1.9-cm thick steaks were more desirable than 2.5 and 3.8-cm BROIL steaks as rated by consumers for overall desirability, tenderness, and juiciness, and were more tender as evaluated using WBSF and SSF (P < 0.5). The GRILL method was among the most highly rated for consumer overall desirability, and no significant difference was found existed between THICK treatments. Consumer overall desirability ratings, consumer tenderness ratings and SSF values for the PAR+MARK cookery method had, more desirable values for 3.8-cm thick steaks compared to 1.9 and 2.5-cm thick steaks. The MARK+COOK method was rated the highest for consumer overall desirability, tenderness, juiciness, and had the lowest SSF and WBSF values (P < 0.5). The MARK+COOK method was the most likely to offer consumers a desirable eating experience at steak thicknesses of 2.5 and 3.8-cm thick. The PAR+MARK method was more likely to result in a more positive eating experience as steaks were cut thicker (3.8-cm) as demonstrated by consumer ratings for overall desirability. The GRILL method had the least amount of variation in consumer ratings for overall desirability between steak thicknesses for positive eating experience. Cookery method and steak thickness should be chosen in the correct combination in order to deliver consumers with a positive eating experience in food service industry.
Open Access
Discovering dimensional differences among Holstein and conventional beef middle meat cuts and consumer preferences for appearance
(Colorado State University. Libraries, 2014) Steger, Jessica Renee, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Tatum, J. Daryl, committee member; Pendell, Dustin L., committee member
To view the abstract, please see the full text of the document.
Open Access
Discovering ground beef performance through "premium grind" concepts
(Colorado State University. Libraries, 2013) McHenry, Jordan Helaine, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Tatum, J. Daryl, committee member; Engle, Terry E., committee member; Frasier, W. Marshall, committee member
Four independent experiments were conducted to evaluate performance of ground beef from various sources and production techniques. Flavor and texture of 7 different beef products and the effects of dry-aging were evaluated and quantified by descriptive sensory analysis, fatty acid composition, and volatile compound composition. Beef products evaluated included chuck shoulder clods (NAMP 114), chuck boneless short ribs (NAMP 130), whole briskets (NAMP 120), loin tenderloin tips (NAMP 1190C), loin top sirloin caps (NAMP 184D), round sirloin tip knuckles (NAMP 167), and 81/19 chuck sourced trimmings. Fresh (100% un-aged), 100% dry-aged, and 50% fresh/50% dry-aged trimmings were used to evaluate the effects of dry-aging on ground beef performance. Furthermore, the effects of grinder plate size, blend time, and patty-forming technique were evaluated and quantified by descriptive sensory analysis and objective instrument measurement. Additional treatments compared common grocery store practices of grinding bench trimmings versus re-grinding previously ground chubs. Trained panelists evaluated ground beef patties from each treatment for 10 different flavor notes, including beefy/brothy, browned/grilled, buttery/beef fat, bloody/metallic, gamey, earthy/mushroom, nutty/roasted nut, livery, sour/acidic, and bitter, as well as 7 different texture characteristics, including hardness, cohesiveness, tenderness, connective tissue, particle size, moisture content, and beef fat/oily mouthfeel. In addition, samples were analyzed to determine fatty acid composition of raw products and volatile compounds formed during cooking. No single trimming source evaluated in this study outperformed patties comprised of 81/19 chuck sourced trimmings. Notably, briskets and sirloin caps were ranked comparably to 81/19 trimmings in the desirable flavor attributes of beefy/brothy, browned/grilled, and buttery/beef fat, whereas tenderloin tips were rated lowest in the same desirable flavors. Dry-aged beef samples produced the most complex flavor profile with the highest panel ratings for earthy/mushroom and nutty/roasted nut flavors, and had high scores for browned/grilled flavor. Grinder plate size and patty-forming technique affected perceived texture differences. Panelists indicated that ground beef patties produced with smaller sized grind plates were softer, more tender, and had a smaller particle size. In agreement, objective measures of texture showed lower peak loads for patties produced with smaller sized grind plates. Patties made with a Formax (Formax F6, equipped with the 2874-6 plate, Mokena, IL) were softer and more cohesive, while patties made with the vacuum stuffer (Model VF50, Handtmann, Germany) equipped with a portioning device were more crumbly but also ranked higher for moisture content and oily mouthfeel. Ground beef patties resulting from the re-ground chubs were perceived to have a greater amount of connective tissue, a larger particle size, greater moisture content, and a greater beef fat/oily mouthfeel. Additionally, objective measures of texture showed greater peak loads for patties from re-ground chubs.
Open Access
Effect of dietary beta-agonist supplementation on live performance, carcass characteristics, carcass fabrication yields, and strip loin tenderness and sensory traits
(Colorado State University. Libraries, 2012) Arp, Travis Steven, author; Belk, Keith, advisor; Woerner, Dale, committee member; Tatum, J. Daryl, committee member; Pendell, Dustin, committee member
Beef steers (n = 3,906) were fed at a commercial feed yard to evaluate the effects of beta-adrenergic agonist supplementation on live performance, carcass characteristics, carcass fabrication yield and strip loin tenderness and palatability. Steers were weighed and ultrasonic carcass measurements were collected for allocation into four feeding blocks. Within each block, approximately 100 steers were assigned two a pen that was assigned one of five treatments, including: No beta-agonist; Ractopamine hydrochloride (RH) fed at 200 mg/hd/d for the final 30 d of finishing (RAC200); RH fed at 300 mg/hd/d for the final 30 d of finishing (RAC300); RH fed as a 400 mg/hd/d top dress for the final 30 d of finishing (RAC400); and Zilpaterol hydrochloride (ZH) fed at 6.8 g/ton beginning 23 d before slaughter, with a withdrawal period starting 3 d before to slaughter (ZIL). The study design included eight replicates (pens) per treatment (two per block). Each feeding block was harvested on consecutive weeks. Each week, carcass parameters were measured and strip loin samples were collected from 18 carcasses per pen (720 total samples) for Warner-Bratzler and Slice Shear Force, and trained sensory analysis. Subsamples of eight carcasses per pen (320 total samples) were selected for whole carcass fabrication yield. Final BW was not affected by treatment (P = 0.2892), but there was a tendency for cattle receiving βAA supplementation to be heavier compared to controls (P = 0.0681). Average daily gain and F:G ratio was improved with treatment of βAA (P < 0.05). Carcasses from the ZIL and RAC400 treatments had the heaviest HCW, and were significantly heavier than CON and RAC200 treatments (P < 0.05). The ZIL treatment also recorded the highest dressing percent and carcasses had the largest LMA compared to all other treatments (P < 0.05). USDA yield grade and marbling score were reduced due to βAA supplementation (P < 0.05). Differences in marbling score reduced the frequency of carcass qualifying for the CAB premium in βAA treated cattle (P < 0.05), while also accounting for a decrease in the frequency of carcasses grading choice and an increase in the percentage of carcasses grading select for cattle receiving βAA supplementation compared to controls (P < 0.05). The percentage of YG1 carcasses was increased and the frequency of YG3 carcasses was decreased due to βAA treatment (P < 0.05). Treatment with dietary βAA elicited the greatest response in subprimal yield in cuts from the round. Zilpaterol treatment carcasses reported the highest total saleable yield, and were greater than all RAC treatments (P < 0.05). Warner-Bratzler and SSF was affected by treatment (P < 0.05), with an increase in shear force values with increased dose and potency of βAA's. Likewise, the percentage of steaks shearing greater than 4.4 and 20 kg for WBSF and SSF, respectively, was increased with βAA supplementation (P < 0.05). Tenderness attributes were ranked lower for steaks from βAA treatments by trained sensory panelists (P < 0.05). There were no differences detected by panelists for juiciness or beef flavor attributes.
Open Access
Effect of packaging during storage time on retail display shelf-life of beef strip loins from two different production systems
(Colorado State University. Libraries, 2016) Luzardo, Santiago, author; Belk, Keith E., advisor; Woerner, Dale R., committee member; Tatum, J. Daryl, committee member; Hess, Ann M., committee member
The objective of this study was to evaluate the influence of packaging during storage of strip loins (to simulate export shipment) from steers fattened on intensive grazing systems (Uruguay; UR) or on high concentrate diet (United States; US) on retail display life color, microbial growth, fatty acids profile, lipid peroxidation and vitamin E content. Four different packaging treatments were applied to UR and US strip loins or steaks during 35 d storage; treatments were applied 7 d following slaughter. After 35 d storage, the samples were evaluated during simulated retail display for 6 d. In block 1, the treatments were: vacuum packaging (VP); low-oxygen modified atmosphere packaging (MAP) with nitrogen (N2) and CO2 (MAP/CO2); low oxygen MAP with N2 plus CO2 and carbon monoxide (CO); VP plus an application of peroxyacetic acid (VP/PAA). In block 2, the treatments were: VP, MAP/CO and VP with ethyl-N-lauroyl-L arginate HCl (LAE) incorporated into the film as an antimicrobial agent (VP/AM). In block 3, the treatments were: VP, MAP/CO2, MAP/CO and VP/AM. Regardless of production system and packaging treatment, mesophilic and psychrotrophic counts of 6.9 to 7.8 log10 CFU/cm2, and 6.7 to 7.7 log10 CFU/cm2, respectively, were obtained at the end of retail display, except for US samples in blocks 2 and 3 (5.5 to 6.3 log10 CFU/cm2). The UR strip loins packaged with MAP/CO had greater (P < 0.05) a* values than product packaged in VP/PA and MAP/CO2 following 6 d of display. For US beef, the MAP/CO treatment resulted in the reddest lean color (P < 0.05) compared to the other three packaging treatments in block 1. In blocks 2 and 3, the UR strip loin steaks packaged in MAP/CO also had the greatest a* values compared to the other three treatments, but no differences (P > 0.05) were detected among the VP treatments and the MAP/CO in the US steaks at the end of retail display. Only system (in block 1, and blocks 2 and 3), and time (in block 1) affected (P < 0.005) lightness (L*). In all blocks, US samples had greater L* values than UR samples (32.6 vs. 28.5; P = 0.0015, for block 1; and 33.4 vs. 31.1; P < 0.0001 for blocks 2 and 3). Vitamin E content in UR steaks, regardless of packaging treatment, was greater (P < 0.05) than US steaks. No effect of packaging treatment (P > 0.05) was observed by country of origin at the different display times in block 1, but UR beef displayed for 0 d from the MAP/CO2 treatment had greater (P < 0.05) vitamin E content than beef from the other three packaging treatments in blocks 2 and 3. Packaging x system, system x time and packaging x system x time interactions were not significant for any of the fatty acids analyzed on this study. Beef from UR had lower (P < 0.05) SFA and MUFA concentrations and greater (P < 0.05) PUFA, n-6 and n-3 concentrations than US beef when evaluated during retail display. Beef from UR developed more detectable (P < 0.05) oxidized odor than US samples while the latter exhibited a greater (P < 0.05) sour odor than UR grass-fed samples. Values from TBARS were influenced by significant packaging x system x time interaction in block 1 (P = 0.0027) and in blocks 2 and 3 (P = 0.0104). In block 1, UR beef had a greater (P < 0.001) TBARS values than US samples on d 0 of display, but TBARS values tended to decrease during retail display and differences almost disappear by the end of the display period. For blocks 2 and 3, TBARS value tended to increase between d 0 to d 6 of retail display in the UR and US samples. Complexity of fresh meat post-mortem chemistry warrants a more comprehensive and systemic approach to maximize shelf-life.
Open Access
Effects of extended postmortem aging on selected beef muscles intended for retail sale
(Colorado State University. Libraries, 2014) Karney, Erin D., author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Tatum, J. Daryl, committee member; Pendell, Dustin L., committee member
In order to mimic beef commonly found in retail supermarkets, paired strip loins (NAMP #180) and top sirloin butts (NAMP #184) were obtained from USDA Choice carcasses with a marbling score ranging from Small00 to Small50 (n = 15) and USDA Select carcasses with a marbling score ranging from Slight50 to Slight99 (n = 15) at a commercial packing plant. Samples were collected from 3 separate groups of carcasses in order to replicate each aging and display period three times. At 48 hours postmortem, paired strip loins and top sirloin butts were portioned into 3-inch sections, vacuum-sealed, and stored 14, 21, 28, 35, 49, or 63 days postmortem. For both strip loin and sirloin sections, once the aging period was designated, the sections were stored in a vacuum-sealed bag at 0°C (± 1°C) and in the dark until their assigned aging period was complete. Two steaks from each aged section for each muscle was placed in a styrofoam tray with a polyvinyl chloride overwrap and placed in a multi-deck retail display case equipped with LED lighting (Hussmann Model No. M3X8GEP) and set at 2°C for 72 hrs. A third steak cut from each aged section was immediately cooked, and Warner-Bratzler shear force (WBSF) analysis was measured to determine the effects of the aging period on tenderness without the display period. During the display period, each steak was evaluated every 8 hours by a minimum of 8 trained panelists for lean color, external fat color, lean percent discoloration, and L* a* b* color values. A trained sensory panel for tenderness and flavor attributes, including off-flavors, also was used to evaluate steaks. As steaks were subjected to longer periods of postmortem aging, WBSF values decreased and trained sensory panel tenderness ratings improved. A 72 h display time reduced (P < 0.05) WBSF values of strip loin and sirloin steaks. A minimum of 28 d of postmortem aging was required to improve the WBSF values of low Choice and Select strip loin steaks compared with the same strip loins steaks aged for 14 d, and a minimum of 35 d of postmortem aging was required to improve sensory tenderness ratings for low Choice and Select strip loin steaks. Strip loin steaks aged up to 28 d before retail display had little impact on display life and the incidence of off-flavors; however, there was no tenderness advantage over 14 d aged steaks from low Choice and Select strip loins. Thirty-five days of postmortem aging were required to achieve an improvement in WBSF compared to that achieved with 14 d aging for low Choice and Select top sirloin steaks, and trained sensory panel scores indicated that at least 49 d of postmortem aging was required to improve the myofibrillar tenderness of low Choice and Select sirloin steaks. Sirloin steaks aged 35 d and beyond produced undesirable lean color scores in as early as the first 24 h of retail display, and top sirloin steaks aged only 14 d and displayed an additional 72 h had relatively intense levels of oxidized and sour/acidic flavors present. Top sirloins cannot be aged for enough time to improve tenderness and maintain a considerable level of display life, and extended aging time is not a viable option for top sirloins intended for retail display and sale.
Open Access
Factors that impact probability of pregnancy when using AI boars
(Colorado State University. Libraries, 2013) Kaysen, Brett L., author; LeValley, Steve B., advisor; Ames, David R., committee member; Dalsted, Norman L., committee member; Schwab, Clinton R., committee member; Tatum, J. Daryl, committee member; Kimberling, Cleon V., committee member
Measurements collected during a period of 3.5 years at Tempel Genetics Inc. in Gentryville, IN were analyzed to evaluate the effects of genetic and environmental factors on pregnancy rate using data from 15,375 parity records of two breeds (Landrace and Yorkshire). Female records utilized in the current study ranged from maiden gilts to mature sows through parity 7. All matings were performed via artificial insemination by semen produced within a boar housing facility also operated by Tempel Genetics. Semen was collected, processed, and evaluated on the farm and was not frozen. Pregnancy rate (measured as probability of pregnancy at 21 days post breeding via ultra-sound) of the females was significantly affected by number of services (P<0.05), season of insemination (P<0.05) and parity category (P<0.05). Interactions of (season by number of services and parity by number of services) were also evaluated. Boar age (P<0.05) and days from collection to insemination (P<0.05) were also significant sources of variation for pregnancy rate, while breed did not significantly affect pregnancy rate. The highest pregnancy rate (94.29%) was observed in sows of the parity category 3-4 that were inseminated with three services and using semen from boars less than 5 years of age. Potential opportunities to optimize these three factors should be evaluated by producers who expect to attain maximum pregnancy rate of sows inseminated using fresh boar semen. A model was also developed in Microsoft Excel format using results from the aforementioned analysis as a tool to assist swine producers in evaluating various management options to enhance pregnancy rate. With the use of this model, smaller producers who do not have access to large amounts of internal data can evaluate the potential impact of implementing different management options evaluated within a typical commercial-based swine enterprise.
Open Access
Identifying and characterizing the influence of cattle production history and lean muscle characteristics on specific beef flavor attributes
(Colorado State University. Libraries, 2016) Adams, Tanner Scott, author; Woerner, Dale R., advisor; Legako, Jerrad F., committee member; Tatum, J. Daryl, committee member; Belk, Keith E., committee member; Enns, Kellie J., committee member
Experiments were conducted on ground beef patties as well as pure fat and lean samples manufactured using various sources and production techniques. Differences among 5 cattle types, 3 muscle types, and 3 lean percentages were evaluated for descriptive sensory analysis, fatty acid composition, volatile compound composition, and amino acid composition. Furthermore, an olfactory detection port (ODP) was used while analyzing volatiles to detect odorous compounds. Cattle types, breed and days-on-feed (DOF), evaluated included F1 Wagyu-Angus crosses (450 DOF), long-fed natural Holsteins (350 DOF), short-fed retail Holsteins (250 DOF), long-fed conventional beef (200 DOF), and short-fed beef (90 DOF). Muscles included in this study were Pectorales profundi (high connective tissue), Longissimus dorsi (intermediate connective tissue), and Psoas major (low connective tissue). Lean percentages of ground beef included 90%, 80%, and 70%. All sources were used in combination as a factorial design with 5 cattle types mixed with 3 muscles at 3 different lean percentages (5x3x3) with one treatment consisting of 45 samples with 5 replications (N=225). Trained panelists evaluated ground beef patties from each treatment and replication for 8 different flavor notes, including beefy/brothy, browned/grilled, buttery/beef fat, bloody/metallic, grassy/fishy, earthy/mushroom, nutlike/roasted nut, and livery/organy. Initial analyses consisted of least-square-means to determine differences among breed, muscle, and lean percentage and the interactions among them. These results were significant (P < 0.05) for two-way and three-way interactions; however, no plausible data could be interpreted from the analysis. Further analyses with principal component analysis were used to determine relationships between amino acids, fatty acids, volatiles, and sensory panels with cattle type and muscle separately. Relationships were identified and used to identify certain attributes as possible contributions to beef flavor. Additionally, nonmetric multidimensional scaling was used to access clustering using pairwise comparisons. This showed significant (P < 0.05) differences among cattle type treatments with small variance between samples while muscle treatments were not significant (P > 0.05) and encountered large variance between samples.
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 member
To view the abstract, please see the full text of the document.
Open Access
Nutrient composition and sensory attributes of beef from grain-finished steers and heifers
(Colorado State University. Libraries, 2013) Acheson, Rebecca Jean, author; Woerner, Dale R., advisor; Tatum, J. Daryl, committee member; Engle, Terry E., committee member; Belk, Keith E., committee member; Bunning, Marisa L., committee member
Over the past decade, nutrient composition of beef became an increasingly important topic both domestically and internationally for the beef industry and its consumers. Beef is an important source of protein, monounsaturated fatty acids, conjugated linoleic acid, vitamins and minerals. Due to evolutionary changes in production practices and fabrication techniques the current nutrient data in the USDA National Nutrient Database for Standard Reference has become outdated. The objectives of these studies were to determine the nutrient composition of ten beef loin and round retail cuts to update the USDA National Nutrient Database for Standard Reference (SR). Seventy-two carcasses representing a national consist of yield grade, quality grade, and genetic type were identified from six regions across the U.S. Beef short loins, strip loins, tenderloins, inside rounds, and eye of rounds (IMPS # 173, 175, 190A, 169A, and 171C) were collected from the selected carcasses and shipped to three university meat laboratories for storage, retail fabrication, and raw/cooked analysis of nutrients. Sample homogenates from each animal were analyzed for proximate composition, as well as fatty acid, cholesterol, vitamin, and mineral content. Data from this study were intended to update SR information regarding the nutrient status of beef and to determine the influence Quality Grade, Yield Grade, and sex classification have on proximate composition. This study identified four Upper Choice, seven Low Choice, and eight Select cuts that qualify for the lean nutrient claim based on cooked separable lean values. Results from the cooked beef loin samples indicate that beef is a good source of iron, vitamin B2, and phosphorus, and an excellent source of selenium, zinc, and vitamins B3, B6, and B12. The nutrient data provided will be utilized to help update nutritional labels of beef products and to help design future dietary interventions that include beef as a protein source.
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 member
Tenderness 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.
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 member
An 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.
Open Access
Quantifying the "aging response" and nutrient composition for muscles of the beef round
(Colorado State University. Libraries, 2010) Dixon, Cheyenne Lee, author; Belk, Keith E., advisor; Chapman, Phillip L., committee member; Tatum, J. Daryl, committee member; Woerner, Dale R., committee member
The objective of this study was to determine the optimal postmortem aging period and nutrient composition for Beef Value Cuts of the round. For the postmortem aging study, 40 USDA Select and 40 premium USDA Choice beef carcasses were selected from a commercial beef packing plant in Colorado over a 12-week period. The bottom and inside rounds were collected from both sides of each carcass for further fabrication into the following muscles: Adductor, Gastrocnemius, Gracilis, Pectineus, and Superficial digital flexor. Each pair of muscles was cut into seven steaks, approximately 2.54 cm in thickness, and vacuum packaged. All steaks were randomly assigned to one of the following aging periods: 2, 4, 6, 10, 14, 21, and 28 days, and placed in refrigerated storage (2°C, never frozen). Upon completion of the designated aging period, steaks were removed from storage, cooked to a peak internal temperature of 72°C, and evaluated using Warner-Bratzler shear force (WBSF). A two-way interaction was detected (P < 0.05) between individual muscle and postmortem aging period. The WBSF of all muscles except the Superficial digital flexor decreased with increased time of postmortem aging. Quality grade did not affect (P > 0.05) WBSF values for the Adductor, Gastrocnemius, Pectineus, and Superficial digital flexor muscles. Exponential decay models were used to predict the change in WBSF from 2 to 28 days postmortem (aging response). The Adductor, Gastrocnemius, Select Gracilis, premium Choice Gracilis, and Pectineus required 21, 14, 23, 23, and 25 days, respectively, to complete the majority of the aging response. To determine the nutrient composition of the Adductor, Gastrocnemius, Gracilis, Pectineus, Semimembranosus, and Superficial digital flexor, bottom and inside rounds were collected from 10 USDA Select and 10 premium USDA Choice carcasses, fabricated into the respective muscles, cut into 2.54 cm cubes, frozen (-20°C), and then homogenized. The Adductor, Gracilis, Pectineus, Semimembranosus, and Superficial digital flexor were analyzed for dry matter, moisture, crude protein, and ash percentages. All muscles were evaluated for lipid percentage and fatty acid and cholesterol composition. When quality grades were combined, all muscles fell into the "extra lean" or "lean" categories specified by USDA guidelines based on the total fat, saturated fat, and cholesterol content present in each cut. Results of this study illustrate the potential for Beef Value Cuts of the round to be sold in foodservice operations and retail stores with marketing emphasis being placed on the exceptional leanness and acceptable tenderness of these cuts.
Open Access
What is quality? The propensity of foreign customers of U.S. pork to pay for pork quality attributes in select export markets
(Colorado State University. Libraries, 2010) Murphy, Ryan Gordon Leon, author; Belk, Keith E., advisor; Pendell, Dustin L., committee member; Tatum, J. Daryl, committee member; Woerner, Dale R., committee member
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