Mountain Scholar :: Browsing by Author "Woerner, Dale R., advisor"

Browsing by Author "Woerner, Dale R., advisor"

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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
Complete nutrient analysis of grain finished and grass finished lamb
(Colorado State University. Libraries, 2016) Gifford, Cody Lynn, author; Woerner, Dale R., advisor; Martin, Jennifer N., committee member; Engle, Terry E., committee member; Belk, Keith E., committee member; Harris, Mary A., committee member
Health conscious consumers continue to search for foods that are nutrient dense. Nutrient labeling of foods allows consumers to select foods based on nutrient composition. The objective of this study was to analyze nutrient composition of eleven raw and cooked grain-finished and grass-finished lamb cuts to update nutrient data in the USDA National Nutrient Database for Standard Reference (SR). Packages of foreshanks, whole legs, sirloin chops, whole loins, loin chops, whole frenched ribs, frenched rib chops, whole ribs, rib chops, whole shoulders, shoulder blade chops, shoulder arm chops, stew meat, and ground lamb (IMPS # 210, 234, 1245, 232A, 1232A, 204D, 1204D, 204B, 1204B, 208, 1207B, 1207A, 295 and 296) were collected in original packaging from three U.S. suppliers during all seasons. Packages were shipped to Colorado State University Meat Laboratory for retail cut dissection, cooking, and nutrient analysis. Single composites of separable lean homogenates were formed for each cut for analysis of proximates, fatty acids, vitamins and minerals. Single composited seam and external fat from each cut were analyzed for proximates, fatty acids, vitamins and minerals. Results from this study generated greater fatty acid profiles, resulted in lower fat content, established nutrient composition for grass-finished cuts and provided updated nutrient composition for inclusion into the SR.
Open Access
Consumer preferences for beef flavor
(Colorado State University. Libraries, 2014) Webb, Megan Jean, author; Woerner, Dale R., advisor; Belk, Keith E., advisor; Pendell, Dustin L., committee member; Engle, Terry E., committee member
For consumer satisfaction to occur, beef retailers and producers must continuously provide beef that contributes to desirable beef flavor. The objectives of this research was: 1) determine the consist of preference for beef flavors resulting from various production practices among beef consumers, 2) develop a true ranking of preference via best-worst (B/W) scaling, and 3) identify the proportion of preference for beef product categories resulting from various production practices. Nine consumer panels were conducted in three different geographical locations (eastern, central and western US). Consumer beef flavor preference was determined using B/W scaling, multinomial logit, and random parameter logit models in SAS® MDC. Proximate analysis and consumer ranking of attributes when making beef purchases was analyzed using an ANOVA, then means were separated using least squares means in SAS® and consumer demographic information was analyzed using PROC GLIMMIX. Overall, the four samples with the greatest percentage of lipid, F-1 Wagyu x Angus (20.2%), wet-aged upper two-thirds USDA Choice (15.6%), USDA Prime (14.7%), and dry-aged upper two-thirds USDA Choice (13.7%) resulted in a greater percentage of preference for flavor than product categories with a lower percent lipid, low USDA Choice (12.5%), USDA Select (11.9%), beef derived from domestic grass-fed cattle (6.8%); and beef derived from Uruguayan grass-fed cattle (4.5%). Results suggest the incorporation of Wagyu genetics, breeding cattle for a greater propensity of lipid, and grain finishing market beef cattle should result in a more preferred beef flavor characteristic. Results from demographic preference show females, Millennials (18 - 34 years of age), and respondents with an average or higher household income are more likely to consider beef derived from Uruguayan grass-fed cattle as their least preferred sample. Results from consumers making beef purchasing decisions show marbling level (3.8) and USDA grade of product (4.2) are moderately important and if the product was grass-fed vs. grain-fed (7.5) is the least important beef characteristic. Demographic information shows Baby Boomers (over 50 years of age) prefer beef derived from domestic grass-fed cattle (10.3%) more than both Generation X (6.0%; 35 - 50 years of age) and Millennials (7.1%; P < 0.05). Baby Boomers (18.6%) also prefer dry-aged upper two-thirds USDA Choice more than Millennials (13.6%; P < 0.05).
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 USDA carcass maturity on eating quality of beef from fed steers and heifers that have been classified into maturity groups using dentition
(Colorado State University. Libraries, 2015) Semler, Megan Lynn, author; Woerner, Dale R., advisor; Tatum, J. Daryl, advisor; Belk, Keith E., committee member; Enns, Kellie J., committee member
Objectives were to compare sensory properties of LM steaks from A maturity and B maturity or older carcasses that were produced by grain finished steers and heifers classified as less than and greater than 30 months of age at the time of slaughter by dentition. Carcasses were selected to represent 2 dentition groups, 2 maturity groups, and 3 marbling categories within each dentition x maturity group resulting in 12 dentition x maturity x marbling subclasses; each subclass consisting of 50 carcasses. Dental age groups consisted of carcasses classified as less than or 30 months of age (MOA) or 30 MOA or older by dentition. Maturity groups consisted of carcasses classified by USDA graders as either A⁰⁰ to A⁹⁹ overall (A) maturity or B⁰⁰ to D⁹⁹ overall (B-D) maturity; marbling categories consisted of carcasses with instrument marbling scores of Slight (SL), Small (SM), or Modest ⁰⁰ to Moderate ⁹⁹ (MT-MD). Carcasses were selected in pairs so that each carcass selected to represent the B-D maturity group was paired with an A maturity carcass of the same sex and similar marbling score (± 50 marbling units.) Strip loin (LM) steaks were obtained from both sides of each carcass. After a 14-d aging period, 1 LM steak was evaluated for Warner-Bratzler shear force (WBSF) and slice shear force (SSF). The other LM steak was used for sensory analysis by a trained descriptive attribute panel. No differences (P > 0.05) were detected in WBSF, SSF, or sensory panel ratings for tenderness juiciness, or flavor between LM steaks from carcasses classified as A maturity vs. steaks of carcasses classified from B-D maturity. Sex class influenced (P < 0.05) WBSF and sensory panel tenderness. As degree of marbling increased, sensory tenderness, juiciness, meaty/brothy flavor, and buttery/beef fat flavor increased (P < 0.05) while bloody/serumy flavor, WBSF and SSF decreased (P < 0.05). There was a significant interaction between dental age group and marbling category for SSF and panel tenderness ratings, where cattle classified as 30 MOA or older with a slight degree of marbling produced the toughest (P < 0.05) LM steaks. Within the SM and MT-MD marbling categories dental age had no effect. Results from this study suggest that USDA quality grades could be effective at determining eating quality differences to grain-finished cattle with a dental age less than 30 mo old at the time of slaughter if the A and B-D maturity groups were combined and quality grades were assigned only by marbling. In grain-finished cattle 30 mo or older at the time of slaughter the evidence was not sufficient to make conclusions.
Open Access
Effects of antimicrobial interventions on food safety and an assessment of the Colorado pork supply
(Colorado State University. Libraries, 2018) Britton, Brianna C., author; Woerner, Dale R., advisor; Belk, Keith E., advisor; Geornaras, Ifigenia, committee member; Prenni, Jessica E., committee member
To view the abstract, please see the full text of the document.
Open Access
Effects of antimicrobial treatments on food safety, quality and shelf-life of beef
(Colorado State University. Libraries, 2019) Swenson, Joanna Kristine, author; Belk, Keith E., advisor; Woerner, Dale R., advisor; Geornaras, Ifigenia, committee member; Narayanan Nair, Mahesh, committee member; Prenni, Jessica E., committee member
To view the abstract, please see the full text of the document.
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
Evaluations that increase value for pork export products
(Colorado State University. Libraries, 2017) Sewald, Dan, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Mason, Gary, committee member
Experiment 1: An evaluation of the suitability of porcine lung tissue for human consumption. This study was conducted to provide evidence of the safety of pork lungs for human consumption via an assessment of prevalence of potentially pathogenic bacteria and infectious agents. Specifically, the goal was to collect evidence that could be used to petition the current regulation disallowing use of pork lungs for human food. Pork lungs have been labeled by the U.S. Meat Export Federation as a widely consumed product across Asia as well as South and Central America. It was believed that there is profit potential in saving pork lungs and exporting them to specified countries. Pork lungs must first be deemed safe and edible before they can be sold on the export market. Lungs (N = 288) were collected from a total of six federally inspected young market barrow/gilt or sow processing facilities. In an attempt to obtain a representative sample of production at each facility on a given day, lungs were randomly selected throughout the entire production day. All collected lungs were removed and processed using aseptic techniques to prevent any exogenous contamination. Lung samples were tested for the presence of pathogens and other physical contamination. Lungs did not test positive for Yersinia spp., Influenza, or Mycobacterium spp., and they contained low yeast and mold counts. However, multiple lung samples collected from both barrows/gilts and mature sows tested positive for Salmonella spp., Shiga toxin-producing Escherichia coli, Campylobacter, and Streptococcus suis. Also, half of the samples collected were found to contain aspirated plant material within the airways of the lungs. These results suggested that pork lungs are not safe and should not be saved for human consumption. Experiment 2: Pork Fibrin used as a meat binder in pork variety and offal meats. Fibrin is a cold set binding product that is created by recombining the two blood components of thrombin and fibrinogen. This study was conducted as a proof-of-concept to validate using fibrin derived from pork blood to create value-added export items from various pork offal and variety meats, hence adding value to both pork blood and pork offal/variety meats. Fibrin currently is marketed as Fibrimex® by Sonac, but the patent for producing fibrin expired leaving potential for U.S. pork operations to begin to produce their own fibrin and use it to create their own value-added products. A total of eight finished products were created in this study using Fibrimex® and pork offal/variety meats. Products for which use of the fibrin complex proved useful included a boneless baby back rib-like product made from pork jowl, a steak-like product made from diaphragms, a boneless hock, a log of skinned pork tongues, a pinwheel with pork diaphragm and cheese, a steak made from course ground heart and back fat, fresh bacon made from pork jowl, and a bung roll stuffed with liver, heart, and kidneys. These products were examples that demonstrated the binding capabilities of fibrin on offal/variety meats that differed in texture. All products were believed to have potential as successful export items. It was noted that fibrin could be added to many other meats to create additional products, including products that are of value within our country's own markets.
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
Impact of unconventional beef carcass rib separation, oven temperature, and degree of doneness on eating quality of beef
(Colorado State University. Libraries, 2016) de Paula e Mancilha, Talita, author; Belk, Keith E., advisor; Woerner, Dale R., advisor; Martin, Jennifer, committee member; Heuberger, Adam, committee member
To view the abstract, please see the full text of the document.
Open Access
Influence of post-mortem aging time and method on flavor and tenderness of beef, and comparison of retail cutting yields, times, and value in thirteen beef subprimals from beef and Holstein cattle
(Colorado State University. Libraries, 2018) Foraker, Blake Austin, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Engle, Terry E., committee member; Heuberger, Adam L., committee member
The objective of this study was to identify flavor and tenderness differences in beef aged for different lengths of time and using different methods. Strip loin sections from commodity, USDA Choice beef carcasses (n = 38) were randomly assigned to 1 of 8 aging treatments: 1) 3 d wet-aged; 2) 14 d wet-aged; 3) 28 d wet-aged; 4) 35 d wet-aged; 5) 49 d wet-aged; 6) 63 d wet-aged, 7) 21 d dry-aged; and 8) 14 d wet-aged followed by 21 d dry-aged (combination). Trained sensory panelists rated the cooked product for flavor and textural attributes, and samples were evaluated for Warner-Bratzler and slice shear force, fatty acid composition, amino acid composition, and volatile flavor compounds. Wet-aging of beef up to 35 d caused no changes (P > 0.05) in flavor notes. However, beef wet-aged for 49 d or longer was rated lowest (P < 0.01) for the attribute of beef flavor ID and greatest (P ≤ 0.02) for metallic, sour, oxidized, nutty, musty/earthy, and liver-like. No differences (P > 0.05) were identified between wet-aging, dry-aging, or the combination of both for any flavor attributes. Fatty acid profiles did not differ (P > 0.05) by aging length of time or method. Concentrations of amino acids and volatile flavor compounds increased (P < 0.01) during the wet-aging period, but minimal differences in these compounds were noted between wet- and dry-aged beef. Additionally, beef that was wet-aged for 3 d was toughest (P < 0.01). Nonetheless, tenderness improvement only occurred up to 28 d of wet-aging, where no subsequent differences (P > 0.05) were noted. Results suggested that wet-aging to extreme lengths of time may have a dramatic effect on flavor profile of beef, without necessarily improving tenderness. Additionally, eating quality characteristics do not necessarily differ between wet- and dry-aged beef. Holsteins comprise approximately 20% of the U.S. fed beef slaughter, and the carcass characteristics of Holsteins tend to differ (on average) from those of traditional beef breeds. Retail cutting yields, cutting times, and resulting value were evaluated in thirteen subprimal cuts from carcasses of fed Holstein (n = 398) and beef-breed (n = 404) origin. Generally, subprimals from carcasses of beef-breeds were heavier (P < 0.05) than those derived from Holsteins. Greater (P < 0.01) saleable yields of retail cuts were noted for ribeye rolls, short loins, and inside rounds (individual muscle) from carcasses of Holsteins, and bottom round flats from carcasses of beef-breeds. Saleable yields of all other subprimal cuts did not differ (P > 0.05) between cattle types. Only the amount of time taken to cut center-cut top sirloin butts derived from beef-breeds were faster (P < 0.01) than those for cuts from carcasses of Holsteins; in all other instances, times for cutting subprimals derived from Holstein carcasses were either faster (P < 0.05) or not different (P ≥ 0.05). Retail prices among cuts from differing breed types were minimal, but true differences (P < 0.05) in cutting yields for ribeye rolls and short loins from carcasses of Holsteins may generate greater values to a steak cutter or retailer. Such advantages could be attributed to smaller, more manageable, and leaner cuts produced from carcasses of Holsteins. Therefore, further research regarding retail cutting differences between cattle types may provide insight for operations seeking maximum retail yields and profit.
Open Access
Mapping temperature decline in beef cattle during conventional chilling
(Colorado State University. Libraries, 2019) Klauer, Brenna Lynne, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Nair, Mahesh N., committee member; Bonanno, Alessandro, committee member
A continued increase in beef carcass weights has likely caused need to adjust chilling practices in order to chill carcasses appropriately with respect to food safety and beef quality. The objectives of this study were to track continuous temperature decline of beef carcasses of varying size, gain insight on how fat thickness and carcass size affect overall chilling rates, and to model temperature decline in deep muscle tissue of 6 muscles and one beef carcass surface location. Temperature recorder thermocouples were placed in 7 carcass locations and temperature was measured every 30 seconds from post electrical stimulation until the carcasses were removed from the postmortem chilling coolers (hot boxes) to be graded. Carcass temperatures were measured at the geometric center of the 1) brisket/plate (deep pectoral), 2) deep chuck (medial side of scapula/clod heart), 3) deep tissue (Semimembranosus), 4) Gluteus medius (Sirloin), 5) Longissimus dorsi at the 12th rib, 6) surface (5mm under the fascia) at the 11th rib, 7) Psoas major (Tenderloin), and 8) ambient per group of carcasses. Carcasses were classified into groups consisting of (1) light (650- 750 pounds), (2) medium (850-950 pounds), and (3) heavy (1050 to 1150 pounds) hot carcass weights. Surface temperatures from all weight categories reached levels below 4˚C within 24 hours of chilling. In the deep tissue (SM), Gluteus medius, and Longissimus dorsi carcass locations, differences in temperature between light versus medium and heavy weight ranges at the final hour of chilling (hour 28) were detected (P < 0.05). At hour 28, no differences (P ≥0.05) were detected among surface, deep pectoral, Psoas major, or deep chuck locations. At hour 28, light weight carcasses reached below the recommended chilling target of 7˚C in the deep tissue location; however, the medium and heavy range carcasses never declined below 7˚C. When larger carcasses are not chilled adequately, potential quality implications exist including reduced quality grades, increased carcass weight loss due to shrink, and fabrication issues. Therefore, beef processing facilities should consider sorting cattle before chilling in order to maximize the quality of the products being processed.
Open Access
Nutrient analysis of ten raw U.S. beef variety meat items and beef flavor myology
(Colorado State University. Libraries, 2018) Kesterson, Hannah Faith, author; Woerner, Dale R., advisor; Belk, Keith E., committee member; Engle, Terry E., committee member; Bellows, Laura L., committee member
Many factors play a role in decision-making related to food and diet; these are closely linked to preferences and personal values in populations with access to a safe and affordable food supply. Many consumers value both nutrition and flavor preferences when making individual choices that ultimately comprise their overall diet pattern. Therefore, it is critical to maintain current, valid information regarding both the sensory profile and nutrient content of foods in the marketplace. Two studies were performed on edible portions of beef carcasses; the first evaluated nutritional value of beef variety meat items in order to update the United States Department of Agriculture (USDA) Food Composition Database. Nutrition information in databases maintained by the USDA is used as groundwork by various groups for several purposes, including nutrition monitoring activities, research, policy creation, and nutritional labeling. However, up-to-date nutrition information is not available for beef variety meat items. Therefore, the objective of this study was to expand availability of nutrient data for beef variety meat items. Beef heart, liver, kidney, tongue, honeycomb tripe, oxtail, marrow bones, testicles, blood, and bone broth were obtained from facilities in the United States. Standardized procedures were used to dissect and homogenize samples. Nutrient analysis occurred at USDA-Agricultural Research Service (ARS) approved laboratories using validated methods and standards. Each of the variety meat items in this study qualifies for at least one "Good Source" or "Excellent Source" labeling claim as defined by the USDA based on the proportion of separable lean component. "Good source" indicates that a product contains 10-19% of the Daily Value (DV) or Recommended Daily Intake (RDI) per Reference Amount Customarily Consumed (RACC) for that nutrient, while "Excellent Source" designates that the food contains at least 20% of the DV or RDI per RACC for that nutrient. Additionally, Vitamin K2 has been studied recently to ascertain beneficial effects on human health, and this nutrient was present in all samples analyzed. This study provides current, analytically-derived nutrient information for U.S. beef variety meat items. Results reflect that these variety meat items could be beneficial in providing essential vitamins and minerals as a component of a healthy diet. This data will be valuable for use by the meat industry, those selling variety meats, researchers, dietetic professionals, and consumers. The objective of the second experiment was to evaluate effects of quality grade, final internal temperature, and cooking method on sensory profile of five beef muscles: rectus femoris, gluteus medius, infraspinatus, triceps brachii, and teres major, in order to characterize sensory characteristics of these cuts. Two quality grades (USDA Select, Upper 2/3 Choice/Top Choice), three cooking methods (grill, pan grill, oven roast), and three final internal temperatures (58.3°C, 70°C, and 80°C) were included; each of 102 unique treatment combinations were replicated six times. Vacuum packaged beef was purchased directly from a commercial beef harvest facility, fabricated 14 days post-production, and frozen at -20°C until analysis. Each sample was rated by a trained sensory panel for flavor, tenderness, and juiciness factors. Although muscles were not compared directly, muscle differences did exist relative to treatment effects. Degree of doneness had the greatest impact across all muscles evaluated, with higher final temperatures related to greater (P < 0.05) beef ID, browned, and roasted notes in most muscles and decreased (P < 0.05) tenderness. Additionally, panelists rated samples as having greater amounts of bloody/serumy, metallic, and sour flavors (P < 0.05) when cooked to lower end-point temperatures. Cooking method affected flavor note ratings for all muscles, with oven roasting producing increased (P < 0.05) cardboardy, earthy/musty, and sour flavors, whereas pan grilling resulted in more intense bitter and burnt flavors (P < 0.05). Quality grade had a minimal impact on the muscles included in the study. Association of volatile aromatic compounds with specific treatments also varied based on muscle. Overall, the 80°C and pan grilling treatments were related to the most volatile compounds compared to other treatments; primarily pyrazines, alkanes, and alkenes. These results highlighted the importance of understanding the properties of individual cuts in order to best utilize them for a positive eating experience. In combination with previous research, these data will be used to develop a resource that characterizes sensory characteristics of lesser-utilized beef cuts to benefit the meat industry, foodservice operations, in-home cooks, and ultimately beef consumers.
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
Relationships between USDA camera-based quality grades and beef sensory attributes
(Colorado State University. Libraries, 2011) Emerson, Mallory R., author; Woerner, Dale R., advisor; Tatum, J. Daryl, advisor; Belk, Keith E., committee member; Pendell, Dustin L., committee member
This study quantified relationships of recently adopted camera-based USDA beef quality grades to LM sensory attributes and shear force. Heifer and steer carcasses (n = 718, all A-maturity) were selected at beef processing plants in CO, KS, NE, and TX, using marbling scores determined by on-line camera grading systems, to represent 7 marbling degrees: Traces (TR), Slight (SL), Small (SM), Modest (MT), Moderate (MD), Slightly Abundant (SA), and Moderately Abundant (MA). Strip loin steaks were obtained from both sides of each carcass and aged for 14 d. One steak was used to obtain Warner-Bratzler shear force (WBSF) and slice shear force (SSF) measurements; the other steak was evaluated by a trained sensory panel for juiciness, tenderness, detectable levels of several flavors (meaty/brothy, buttery/beef fat, bloody/serumy, livery/organy, and grassy), and overall sensory experience (negative vs. positive). Camera marbling score explained 45, 40, 32, 71, and 61% of the variation in panel ratings for juiciness, tenderness, meaty/brothy flavor intensity, buttery/beef fat flavor intensity, and overall sensory experience, respectively. Increased degree of marbling resulted in steaks having greater (P < 0.001) juiciness, tenderness, meaty/brothy flavor intensity, and buttery/beef fat flavor intensity. The likelihood of a steak delivering a positive sensory experience also became greater (P < 0.001) as degree of marbling increased (MA = SA > MD = MT > SM > SL > TR). Nearly all (98 to 99%) of the steaks with MA and SA marbling, and most (between 80 and 90%) of the steaks with MD and MT marbling received positive ratings for overall sensory experience compared with 62% of the SM steaks, 29% of the SL steaks and 15% of the TR steaks. Steaks produced by steers had lower (P < 0.05) WBSF and SSF values and were generally rated as more tender by sensory panelists than steaks produced by heifers, but the effect of sex on panel tenderness was significant only within the TR category. Comparison of 2 methods for determining camera-based quality grades (i.e., use of original camera grade lines, based on marbling assessments of USDA grading experts vs. use of adopted camera grade lines, based on marbling assessments of field graders) showed that both methods of grade placement effectively stratified carcasses into grades that differed (P < 0.05) with respect to steak juiciness, tenderness, and flavor, with little discernible difference between methods.
Open Access
Special-fed veal: separable components, proximate composition, and nutrient analysis of selected raw and cooked, wholesale and retail cuts
(Colorado State University. Libraries, 2014) Perham, Carlie Claire, author; Woerner, Dale R., advisor; Belk, Keith E., advisor; Engle, Terry E., committee member; Delmore, Robert J., committee member; Foster, Michelle T., committee member
Nutritional qualities of consumer foods are of great importance in improving health. The American obesity epidemic and resulting government recommendations for the decrease in the consumption of foods with high fat and sodium content resulted in an increase in consumer awareness of nutrition. In 2010, the Food Safety Inspection Service published the final rule "Nutrition Labeling of Single-Ingredient Products and Ground or Chopped Meat and Poultry Products" (75 FR 82148) requiring nutrient facts for individual retail cuts be labeled, effective January 1, 2012, under revisions to the Code of Federal Regulations (CFR) for "Nutrition labeling of meat and meat food products" (9 CFR 317.300). Veal products are included in the section regarding the "Identification of major cuts of meat products", which specifies cuts required to have a nutrition label, including veal (9 CFR 317.344). In order to supply veal producers and retailers with nutritional label information, and therefore provide consumers with accurate nutritional information, it is necessary to analyze modern and prevalent veal retail cuts for nutrient content. Ten raw and cooked special-fed veal cuts from six different suppliers of United States-sourced veal were analyzed for nutrient contents. Veal has improved in many aspects of nutrient composition compared to values used in the current United States Department of Agriculture (USDA)-Agriculture Research Service (ARS) Nutrient Database Standard Reference 26 (SR-26). According to USDA federal regulations (9 CFR 317.362), leg cutlets, loin chops, and shank cross-cuts (osso buco) can be labeled under the USDA classification of "Extra Lean" with less than 5g total fat, 2.5g or less of saturated fat, and less than 95mg of cholesterol. Additionally, shoulder blade chops were considered "Lean", having less than 10g fat, less than 5 g of saturated fat, and less than 95 mg of cholesterol per 100 g. The American Heart Association "Heart Check" requirements are met by leg cutlets, loin chops, and shank cross-cuts. Compared to SR-26 data, cholesterol levels declined by 30%. Veal provides an "excellent" source of: Vitamins B2, B3, B6, B12; selenium, zinc, phosphorus, and copper. Additionally, veal is a "good" source of Vitamin D, iron, and potassium. These results provide nutrition facts for consumers to use in conjunction with common cookery methods like grilling- which currently is not an option for veal when searching for foods on the current SR. Additionally, values for choline and Vitamin D are now available for veal. Vitamin D levels in veal from these data showed that raw and cooked ground veal fulfill the requirements to be labeled as a "good source" of this anti-carcinogenic nutrient, containing more Vitamin D than fortified milk and having close to the same levels of eggs and fish. Veal is a lean, complete protein choice for consumers, providing "excellent" and "good" amounts of protein, vitamins, and minerals.