Loin Chops Research Articles

74 Effects of dietary soy isoflavone supplementation on carcass cutability and meat quality of pigs infected with porcine reproductive and respiratory virus

Abstract The objective was to evaluate the effects of porcine respiratory and reproductive syndrome virus (PRRSV) infection and dietary soy isoflavone supplementation on carcass cutability and meat quality of commercial pigs. Barrows were randomly allotted to experimental treatments that were maintained throughout the study: non-infected pigs received an isoflavone-devoid control diet (NC, n = 22), and infected pigs received either the control diet (PC, n = 20) or that supplemented with total ISF in excess of 1,600 mg/kg (ISF, n = 25). Following a 7-d adaptation, weanling pigs were inoculated intranasally with either a sham-control (PBS) or live PRRSV (1×105 TCID50/mL, strain NADC20). At 1 d postmortem (192–194 days of age; approximately 120kg BW), left sides were separated between the 10th and 11th rib for determination of loin eye area (LEA), backfat thickness (BF), and loin quality (ultimate pH, instrumental color, drip loss, visual color, marbling, and firmness). Loin chops were aged 14 d postmortem prior to Warner-Bratzler shear force (WBSF) determination. Belly width, length, thickness, and flop distance were determined. Data were analyzed as a one-way ANOVA with a model including effects of PRRSV status and dietary treatment, and also with single-df pre-determined contrasts to compare NC and PC (infection status) and PC and ISF (ISF effect within infected pigs). Carcass yield, LEA, BF, and estimated lean percentage did not differ (P > 0.26) among treatments. Loins from NC pigs had increased ultimate pH (P = 0.01), reduced L* scores (P = 0.005) coupled with darker visual color scores (P = 0.004), were firmer (P < 0.0001), and reduced drip loss (P = 0.01) compared with PC and ISF pigs. However, WBSF did not differ (P = 0.51) among treatments after 14 d of aging. Bellies from NC pigs were more firm compared with bellies from PC and ISF pigs (P < 0.01). These data suggest PRRSV infection and soy isoflavone supplementation do not alter carcass characteristics but may marginally reduce loin and belly quality.

356 Young Scholar Presentation: An applied approach to studying heat stress: Effects of cyclic heat and zinc supplementation on body temperature, gut health, and pork quality

Abstract Heat stress (HS) has depletory effects on intestinal morphology, induces metabolic changes, and disposes pigs to oxidative stress. Zinc has roles in gut health, nutrient and insulin mediated metabolism. To better understand the effects of cyclic heat and dietary Zn supplementation on gut integrity, carcass composition, and pork quality, commercial crossbred mixed-sex pigs (n = 400; initially 72.2 kg) were housed under either thermoneutral (TN; 18.9–16.7°C) or cycling HS conditions simulating chronic summer heat (30°C/26.7°C for 12h:12h on days 24–65) with acute heat periods of 32-33°C/29-30°C for 12h:12h on days 21–24, 42–45, and 63–65. Treatments were arranged in a 2×2×2 factorial with main effects of environment (HS vs. TN), added Zn level (50 vs. 130 mg/kg available Zn), and added Zn source (inorganic from ZnO vs. organic from Availa®Zn; Zinpro Corp, Eden Prairie, MN). Relative to TN, HS elevated (P < 0.050) body temperatures during the growing period. Heat stress was correlated with ileal villus height (r=-0.51, P = 0.015) and HSP-70 expression (r=0.46, P = 0.041). Growth was reduced such that carcasses from HS pigs were lighter (P = 0.011) and exhibited improved carcass quality with higher (P = 0.001) 24-hour loin pH, decreased (P = 0.034) drip loss, and greater (P < 0.050) subjective color and firmness scores compared to TN carcasses. Relative to TN, loin chops and sausage patties manufactured from the HS carcasses had similar oxidative stability (CIE L*a*b* color, 2-thiobarbituric acid reactive substances) throughout a 10-day simulated retail display. The HS induced fatty acid profile differences in the pork product but were not sufficient to shift IV (P > 0.10). Belly firmness and slice lean were also unaffected (P > 0.10) by HS. Zinc supplementation had minimal impact on the carcass quality characteristics studied. Further research is necessary to better understand the impact of HS duration, combination with additional stressors, and refine the ability to utilize thermal monitoring to manage negative impacts of HS.

Effects of feeding juniper as a roughage on feedlot performance, carcass measurements, meat sensory attributes, and volatile aroma compounds of yearling Rambouillet wethers1,2.

The majority of U.S. lambs are born during late winter or early spring, which can create downstream variability in carcass quality if commercial lamb harvest is to be relatively constant throughout the year. Flavor is an important quality determining characteristic of sheep meat and is influenced, in part, by animal age at harvest. However, management practices to mitigate the risk of objectionable flavors in meat from old crop lambs or yearlings are not well known. Yearling (16.8 ± 0.14 mo) Rambouillet wethers were assigned to 1 of 3 treatment groups, which consisted of feeding a 20% ground sorghum-sudangrass hay diet for 40 d (JUN0; n = 10), a 20% ground juniper diet for 40 d (JUN40; n = 10), or a 20% ground hay diet for 20 d followed by a 20% ground juniper diet for 20 d (JUN20; n = 10). Wethers were harvested on day 41 and a whole bone-in loin and a boneless inside leg roast were fabricated from one side each of carcass. After grilling (loin chop) or convection air roasting (leg roast), trained sensory panel evaluation and measurement of aroma volatiles by gas chromatography/mass spectrometry were performed. Treatment diet did not affect (P ≥ 0.17) wether feedlot performance, dressing percentage, or loin eye area. However, wethers fed JUN0 tended (P = 0.06) to have greater back fat depth than wethers fed JUN20 or JUN40. No trained sensory panel trait of loin chop samples was affected (P > 0.10) by treatment. Leg roasts from JUN0 and JUN20 wethers had greater (P = 0.01) lamb identification sensory score than JUN40. Benzaldehyde, 1-heptanol, and 1-octanol concentrations were greater (P < 0.05) and decanal and nonenal concentrations were less (P < 0.05) in loin chops from JUN0 compared with JUN40 wethers. Additionally, the terpenes cedr-8-ene, gamma muurolene, and widdrene tended to be greater (P < 0.07) in loin chops from JUN20 and JUN40 than JUN0 wethers. The 2-pentyl-furan concentrations were greatest (P = 0.03) in leg roasts from JUN40 wethers. Like the loin chops, cedr-8-ene, gamma-muurolene, toluene, and widdrene were greater (P < 0.05) in leg roasts from wethers fed either of the juniper diets compared with JUN0. Yearling wethers can be finished on a feedlot diet containing 20% juniper for up to 40 d prior to harvest with no impact on feedlot performance, carcass characteristics, nor negative impact on sensory attributes or volatile compounds of either grilled loin chops or roasted legs.

National Retail Benchmarking for Pork 2018

ObjectivesThe objective of this study was to quantify pork quality attributes in the retail meat case nationwide. Similar evaluations were conducted in 2012 and 2015. The comparisons of the benchmarking projects show trends in pork products in nationwide retail stores.Materials and MethodsEighty-five stores representing 26 retailers in 15 cities were visited. Subjective color score (1–6) and subjective marbling score (1–10) on center-cut loin chops was assessed by an experienced grader under lighting of the self-serve meat case. Four individual loin chops with at least 50% lean exposed were randomly selected for evaluation from ten retail packages for each brand and enhancement type. Preference was given to boneless, 2.5 cm-thick center-cut loin chops where available. Ten additional packages of chops for each brand and enhancement type were evaluated in-store and purchased. Each of the purchased packages were labeled and each chop within a package was identified for later evaluation. The purchased packages were subsequently placed inside a cooler and transported to a temporary lab station where chops were again subjectively evaluated for color and marbling under controlled lighting and evaluated in the center of the loin muscle for instrumental color (CIE L*, a*, and b* color space values) using a calibrated Minolta Colorimeter and a Hunter Colorimeter. Chops were then vacuum sealed and immediately placed in the freezer. The samples were later packed in a cooler with dry ice and shipped to the University of Florida on dry ice. After arrival, they were placed in frozen storage until thawed for cooking and shearing. Chops were weighed prior to and after cooking on open hearth, adjustable heat grills until reaching 65°C then evaluated for slice shear.Data was analyzed using the mixed procedure in SAS (v. 9.4, SAS Institute, Cary, NC). The model included enhancement type (EN or NON), and the interaction between enhancement type as fixed effects. Package nested within store, brand, and purchased (yes or no) was fit as a random effect.ResultsThe USDA AMS defined “Tender” as having a minimum threshold values for slice shear as 20.0 kg and “Very Tender” at 15.3 kg, respectively. Sixteen percent of the instore evaluated and purchased retail packages were enhanced (247 and 119 retail packages, respectively). Means for instore enhanced (EN) and non-enhanced (NON) chops were 2.52 and 2.70 for subjective color and 2.25 and 2.65 for subjective marbling, respectively. Means for chops purchased for EN and NON chops under controlled lighting were: subjective color (2.07 and 2.25), subjective marbling (1.89 and 2.21), Minolta L* (56.35 and 56.86), Minolta a* (15.48 and 15.61), Hunter L (56.99 and 58.69), Hunter a (13.98 and 15.08), cook loss (13.02 and 15.64%), and slice shear (12.68 and 15.63 kg).ConclusionResults indicate extensive variation for color, marbling, cooking loss and tenderness exists in the pork meat case. Enhancement continues to improve tenderness though less enhanced pork is found in the marketplace. However, regardless of enhancement, the average value for slice shear of center loin chops were quite tender.Table 5.

Effects of Increased Pork Hot Carcass Weights. I: Chop Thickness Impact on Consumer Visual Ratings

The objective of this study was to evaluate the effect of increased pork hot carcass weights on consumer visual acceptability and purchase intent ratings of top loin chops cut to various thicknesses in a price labeled versus unlabeled retail display scenario. Pork loins (N = 200) were collected from 4 different hot carcass weight groups: light weight (LT; less than 111.8 kg), medium-light weight (MLT; 111.8 to 119. kg), medium-heavy weight (MHVY; 119.1 to 124.4 kg), and a heavy weight group (HVY; 124.4 kg and greater). Loins were fabricated into 4 pairs of chops of specified thicknesses (1.27, 1.91, 2.54, and 3.18 cm). One chop from each pair was assigned to be packaged with or without a label. Consumers assessed chops for appearance, desirability, and purchase intent. For both appearance and purchase intent ratings, chops from HVY carcasses were given more desirable (P &lt; 0.05) ratings compared to LT chops. Consumers gave greater (P &lt; 0.05) appearance ratings to thicker cut chops. There was a hot carcass weight × chop thickness interaction (P &lt; 0.05) for the percentage of consumers that indicated the chop was desirable overall. Regardless of hot carcass weight group, chops with a thickness of 1.27 cm had the lowest (P &lt; 0.05) percentage of consumers indicate they were desirable overall. A greater (P &lt; 0.05) percentage of consumers indicated “yes” they would purchase chops cut to a thickness of 2.54 cm compared to all other thicknesses. Additionally, there was a greater (P &lt; 0.05) percentage of consumers who indicated they would purchase unlabeled chops compared to labeled chops. These results, within the population sampled, indicate that carcass weight and chop thickness can affect consumer preference and thus should be considered by retailers when marketing fresh pork loin chops.

Correlation of Computer Vision System Data with Traditional Methods of Evaluating Pork Color and Marbling on the Ventral Side on the Whole Loin and on Individual Loin Chops

Correlation of Computer Vision System Data with Traditional Methods of Evaluating Pork Color and Marbling on the Ventral Side on the Whole Loin and on Individual Loin Chops

Characterizing Ham and Loin Quality as Hot Carcass Weight Increases to an Average of 119 Kilograms

The objective was to characterize ham and loin quality of carcasses ranging from 78 to 145 kg (average ∼119 kg). Hot carcass weight (HCW), back fat depth, and loin depth was measured on 666 carcasses. Loin pH, instrumental and visual color and iodine value of clear plate fat (all 3 layers) was measured on approximately 90% of the population. Quality measurements of the ham, 14 d aged loin and chop, and loin chop shear force (SSF) were evaluated on approximately 30% of the population. Myosin heavy chain fiber type determination was completed on 49 carcasses. Slopes of regression lines and coefficients of determination between HCW and quality traits were calculated using the REG procedure in SAS and considered significantly different from 0 at P ≤ 0.05. As HCW increased, loin depth (b1 = 0.2496, P &lt; 0.0001), back fat depth (b1 = 0.1374, P &lt; 0.0001), loin weight (b1 = 0.0345, P &lt; 0.0001), and ham weight (b1 = 0.1044, P &lt; 0.0001) increased. Estimated lean (b1 = –0.0751, P &lt; 0.0001) and iodine value (b1 = –0.0922, P &lt; 0.0001) decreased as HCW increased, where HCW accounted for 24% (R2 = 0.24) of the variation in estimated lean and 7% (R2 = 0.07) of the variation in iodine value. However, HCW did not explain variation in ham quality traits (P &gt; 0.15) and did not explain more than 1% (R2 ≤ 0.01) of the variation in 1 d loin color or pH. Loins from heavier carcasses were more tender (decreased SSF; b1 = –0.0674, P &lt; 0.0001), although HCW only explained 9% of the variation in SSF. Hot carcass weight did not alter (P &gt; 0.22) muscle fiber type percentage or area. These results suggest that increasing HCW to an average of 119 kg did not compromise pork quality.

The Effect of Increased Pork Hot Carcass Weights and Varying Chop Thicknesses on Consumer Visual Appearance and Purchase Intent Ratings of Top Loin Chops

The Effect of Increased Pork Hot Carcass Weights and Varying Chop Thicknesses on Consumer Visual Appearance and Purchase Intent Ratings of Top Loin Chops

Effects of Increased Pork Hot Carcass Weights. II: Loin Quality Characteristics and Palatability Ratings

The objective of this study was to evaluate the effects of increased pork hot carcass weight on loin quality and palatability of top loin chops. Pork loins (N = 200) were collected from 4 different hot carcass weight groups: A light weight (LT; less than 111.8 kg), medium-light weight (MLT; 111.8 to 119.1 kg), medium-heavy weight (MHVY; 119.1 to 124.4), and a heavyweight group (HVY; 124.4 and greater). Following fabrication, chops were assigned to fat and moisture analysis, Warner-Bratzler shear force (WBSF), consumer sensory panels, or trained sensory panels. Chops from the HVY group were rated as more (P &lt; 0.05) tender compared to chops from the LT carcasses. Additionally, chops from the HVY weight group had greater (P &lt; 0.05) consumer overall like ratings compared to chops from both the LT and MLT groups. Carcass weight did not affect (P &gt; 0.05) consumer flavor liking ratings. Hot carcass weight treatment did not contribute (P &gt; 0.05) to the percentage of chops rated acceptable for flavor and overall liking. The greatest (P &lt; 0.05) percentage of samples were rated acceptable for juiciness for chops from the HVY weight group, and the lowest (P &lt; 0.05) percentage of acceptable ratings for tenderness were for chops from the LT weight group. Both initial and sustained juiciness from MHVY carcasses were rated as more (P &lt; 0.05) juicy compared to chops from both MLT and LT carcasses by trained sensory panelists. Additionally, chops from the LT carcasses had the lowest (P &lt; 0.05) myofibrillar tenderness ratings. Chops from MHVY and HVY carcasses were similar (P &gt; 0.05), with greater (P &lt; 0.05) overall tenderness ratings compared to chops from LT carcasses. These results indicate chops from heavier weight carcasses may have improved tenderness and juiciness compared to chops from lighter carcasses.

The Effect of Increased Pork Hot Carcass Weights on Loin Quality and Palatability

ObjectivesThe objective of this study was to evaluate the effects of pork hot carcass weight on loin quality and palatability of top loin chops.Materials and MethodsThe pigs in this study were raised to exceed standard market weights. Pork loins (N = 200) were collected from 4 different hot carcass weight groups: light (LT; less than 111.8 kg), medium-light (MLT; 111.8- 119.1 kg), medium-heavy (MHVY; 119.1- 124.4), and a heavy (HVY; 124.4 and greater). Prior to fabrication, purge loss percentage, instrumental color, subjective color and marbling, and pH were taken for each loin. Following fabrication, chops were assigned to fat and moisture analysis, Warner-Bratzler shear force (WBSF), consumer sensory analysis, or trained sensory analysis. For WBSF, consumer, and trained panels, chops were thawed for 24 h prior to analysis. Chops were cooked on clam-shell style grills and removed from the heat with the internal temperature rising to a peak internal temperature of 71°C. Consumers (N = 197) evaluated each sample for tenderness, juiciness, flavor like, and overall liking on 0 to 100 continuous line scales. Consumers were also able to indicate “yes” or “no” if the chop was acceptable for all palatability traits and overall. Trained panelists evaluated each sample for initial juiciness, sustained juiciness, myofibrillar tenderness, connective tissue amount, overall tenderness, pork flavor, and off flavor on similar 0 to 100 continuous line scales.ResultsLoins from all weight groups differed (P 0.05) were found for loin instrumental color, subjective color, subjective marbling, purge loss percentage, pH, WBSF, moisture percentage, fat percentage, and drip loss. Carcass weight did not affect (P > 0.05) juiciness or flavor like ratings but did affect (P 0.05) to the percentage of chops rated acceptable for flavor and overall liking. Chops from the HVY weight carcasses had the greatest (P 0.05) with greater (P < 0.05) overall tenderness ratings compared to chops from LT carcasses.ConclusionThese results indicate that as hot carcass weight increased, there were no negative effects on loin quality, and top loin chops from heavier weight carcasses had improved tenderness and juiciness compared to chops from lighter carcasses. This provides evidence that as the hot carcass weights of pigs in the United States continue to increase there will be no negative effects on quality and palatability.

Special-Fed Veal: Separable components, proximate composition, and nutrient analysis of selected raw and cooked, wholesale and retail cuts

Nutrition research continues to be important for consumers to make informed food purchasing decisions and is used in nutrition policy decisions. The objective of this study was to analyze the nutrient concentration of raw and cooked cuts from special-fed veal calves to update nutrient data in the USDA National Nutrient Database for Standard Reference (SR) Release 27. Packages of wholesale (whole loin roasts, center-cut hindshanks and ground veal) and retail veal cuts (osso buco foreshanks, loin chops, leg cutlets and shoulder blade chops) were randomly collected in original vacuum packaging from six U.S. suppliers. Packages were shipped to the Colorado State University Meat Laboratory for cut dissection, cooking, and nutrient analysis. Composites of lean, external fat and seam fat were formed for analysis of proximate, fatty acid, vitamin and mineral composition. Results from this study identified additional fatty acids, established choline concentration, and provided updated veal nutrient composition information for inclusion in USDA SR 27.

Effects of Marbling and Postmortem Aging on Consumer Assessment of United States Lamb Loin

Consumer sensory analysis was performed to evaluate the effects of three marbling categories [LOW, Intermediate (MED), and HIGH] and 2 postmortem aging categories (21 d and 42 d) on the palatability of lamb loin chops as determined by U.S. consumers and to determine the relationship between marbling, flank streaking, intramuscular fat percentage (IMF), and palatability traits. Marbling and aging did not interact to affect any of the scores for palatability attributes, their acceptances, or the frequency of their overall eating quality classifications (P &lt; 0.05). Consumers rated HIGH treatments (P &lt; 0.05) as more tender, juicier, and with greater flavor liking and overall liking than MED or LOW, which were similar for all traits (P &gt; 0.05). Aging also influenced (P &lt; 0.05) all traits, as consumers scored 21 d samples greater for all palatability traits than their 42 d counterparts. A greater (P &lt; 0.05) percentage of consumers categorized 42 d samples as ‘unsatisfactory’ and fewer as ‘better than everyday’ or ‘premium quality’ than 21 d samples. A larger proportion of consumers categorized HIGH samples as ‘premium quality’ than MED or LOW and fewer called HIGH ‘good everyday quality’ compared to MED (P &lt; 0.05). Flank streaking, marbling score, and IMF were all influenced (P &lt; 0.01) by marbling category in a linear fashion. Increasing marbling score, more so than flank streaking, was positively linked to increasing eating quality scores. Also, tenderness, juiciness and flavor liking are major drivers for consumer sensory scores for overall liking, with flavor liking having the strongest relationship to overall liking of lamb. Overall, consumers preferred HIGH marbling over LOW and MED marbling loin chops, but had difficulty distinguishing between LOW and MED. Furthermore, extending postmortem aging of lamb loin from 21 to 42 d reduced scores for eating quality traits.

Identification of Marbling Gene Loci in Commercial Pigs in Canadian Herds

A genome-wide association study (GWAS) was performed on the intramuscular fat percentage in pork chops in commercially available swine in Canada. The Duroc, Iberian, Lacombe, Berkshire, and Pietrain breeds were crossed with Large White sows, and their F1 offspring were ranked according to the intramuscular fat percentage (IMF %) obtained in their longissimus dorsi (LD) muscle loin chops. The ideal IMF % is considered to be &gt;3%, whereas the average is ~1.5% in North American pork. The genetics of the top 10% and bottom 10% from our sample population were analysed by using 80,000 single nucleotide polymorphism (SNP) microarrays in the GWAS. Our sample population had an average IMF % of 2.5 ± 0.7%, but some pork achieved &gt;7% IMF. GWAS analysis revealed SNP markers which were associated with the highest marbled pork chops on chromosomes 5, 7, and 16. Using the Sus scrofa/ susScr 11.1 map, we determined that the nearest genes were sarcospan (SSPN), Rh-associated glycoprotein (RHAG), and EGF-like fibronectin and laminin G (EGFLAM), which can be linked with muscular dystrophy disorders. We tested a subpopulation of Duroc-sired animals and found a different set of markers close to glycine receptor beta (GRLB) and potassium channel 3 (KCNJ3) on chromosomes 8 and 15. Based on our results, we could achieve pork with a good IMF of &gt;4% from animals commercially bred and raised to standard market weights of 110 kg. The choice of obtaining a good marbling line of pigs is not necessarily breed-specific, but it is line-specific.

The effects of ultimate pH and color on sensory traits of pork loin chops cooked to a medium-rare degree of doneness.

The objective was to determine the effects of pH and color on sensory characteristics of boneless pork loin chops cooked to an internal endpoint temperature of 63 °C. Center cut loins (296 total) from barrows and gilts, 5 different sire lines, and a range in pH of 5.36 through 6.23 were used. Previously, ultimate pH was correlated with sensory characteristics of chops cooked to a medium (71 °C) degree of doneness. Additionally, increasing ultimate pH improved sensory tenderness and juiciness of loin chops cooked to a medium degree of doneness. However, in 2011, the United States Department of Agriculture Food Safety and Inspection Service reduced the recommended final internal cooking temperature of pork chops from 71 to 63 °C (followed by a 3-min rest). The effects of ultimate pH on sensory traits of pork chops cooked to a medium-rare (63 °C) degree of doneness are not known. Therefore, loins were categorized using historical categories based on ultimate pH: >5.95, n = 22; 5.80 to 5.95, n = 75; 5.65 to 5.80, n = 102; 5.50 to 5.65, n = 91; <5.50, n= 6. On 1-d postmortem, loins were evaluated for CIE instrumental L*, a*, b*, visual color, marbling, and subjective firmness. Then, loins were aged in vacuum packages at 4 °C until 16-d postmortem. After aging, loins were cut into 2.54-cm thick chops, vacuum-packaged, and frozen until sensory or instrumental tenderness analysis. One chop was also used to determine extractable lipid. Chops were weighed, cooked to 63 °C, cooled to approximately 23 °C, weighed again to determine cook loss, and then evaluated for Warner-Bratzler shear force. Another chop was cooked to 63 °C internal temperature and served warm to trained panelists to determine sensory traits. Coefficients of determination (R2) were calculated to determine the predictability of ultimate pH and instrumental color on sensory tenderness, juiciness, and flavor. A 1-way ANOVA and means separation test were used to determine specific differences among pH categories. Ultimate pH explained less than 5% of the variation in tenderness and less than 1% of the variation in juiciness or flavor. Furthermore, sensory tenderness did not differ (P > 0.05) among pH categories, except for chops with an ultimate pH > 5.95. Chops with a pH > 5.95 were at least 9.1% more tender (P < 0.05) than chops with a pH < 5.95. Visual and instrumental color were not predictive (R2 ≤ 0.03) of any sensory traits. Overall, pH does not influence sensory traits of pork chops cooked to medium-rare degree of doneness unless pH is at least 5.95.

Influence of feeding thermally peroxidized soybean oil to finishing pigs on carcass characteristics, loin quality, and shelf life of loin chops.

The objective of this study was to evaluate the effect of feeding soybean oil (SO) with varying levels of peroxidation on carcass traits and shelf life of loins. Fifty-six barrows were randomly assigned to 1 of 4 diets containing 10% fresh SO (22.5 °C) or thermally processed SO (45 °C for 288 h, 90 °C for 72 h, or 180 °C for 6 h), each infused with air at a rate of 15 liter/min. Individually housed pigs were provided ad libitum access to feed for 81 d. At 82 d, pigs were slaughtered and hot carcass weight and liver weights were recorded. Carcass characteristics and fresh loin quality were evaluated 1 d postmortem. Loin chops from each carcass were overwrap-packaged and subjected to a 10-d simulated retail display. Daily measurements of L*, a*, b*, reflectance, and visual discoloration were conducted, evaluation of cooking loss and Warner-Bratzler shear force (WBSF) was conducted on chops stored 0, 5, and 10 d, and thiobarbituric acid reactive substances (TBARS) were evaluated on chops stored 0 and 10 d. Shelf life-related data were analyzed as a completely randomized design with repeated measures in time, with storage location (shelf) as a random effect. Carcasses of 90 °C pigs weighed 6.0, 8.6, and 6.9 kg less (P < 0.03) than 22.5 °C, 45 °C, and 180 °C carcasses, respectively. Livers of 90 °C and 180 °C pigs were 14.3% and 11.7%, respectively, heavier (P ≤ 0.02) than those from pigs fed 22.5 °C SO, with livers of 45 °C being intermediate. Livers of 90 °C pigs represented 0.12 percentage units less (P = 0.02) of ending live weight than livers of 180 °C pigs, and 180 °C livers were 0.12 percentage units less (P < 0.01) of ending live weight than those from pigs fed 22.5 °C SO, with 45 °C being intermediate. There was no difference (P ≥ 0.19) in back fat depth, loin muscle area, or estimated carcass lean percentage among SO treatments, nor was there an effect (P ≥ 0.13) of SO on any early post-mortem loin quality traits or loin composition. There was no effect (P > 0.14) of SO on cooking loss, WBSF, L*, a*, b*, hue angle, reflectance, discoloration, or TBARS; however, there was a tendency (P = 0.09) for chops of 45 °C pigs to have greater (P < 0.04) chroma than either 22.5 °C or 180 °C, with 90 °C being intermediate. Overall, feeding SO cooked at 90 °C for 72 h resulted in reduced carcass weight and dressing percentage; however, there was no evidence that feeding peroxidized SO was detrimental to shelf life of loin chops.

186 Comparisons of Correlations Among Early and Aged Pork Quality Traits for Loin Chops Aged As Intact Loins or in Case-Ready Packages.

186 Comparisons of Correlations Among Early and Aged Pork Quality Traits for Loin Chops Aged As Intact Loins or in Case-Ready Packages.

197 Added Fat Fed with 30% Dried Distillers Grains with Solubles to Pigs Alters Fatty Acid Composition in Four Fat Depots but Does Not Change Carcass Composition or Quality.

High inclusion levels of unsaturated dietary fat sources negatively impacts pork fat quality. Thus, the objective of this study was to evaluate supplementing swine diets with saturated animal fats to improve the fatty acid profile of pork carcasses. Forty individually reared barrows (100 kg ± 3 kg, PIC C23 x 337) were randomly assigned to one of five treatments containing dried distillers grains with solubles and 3% added fat to determine the resulting carcass characteristics and fresh pork quality. The treatments included (1) a positive control containing a corn and soybean meal base with 3% choice white grease (PCON), (2) 30% high protein dried distillers grain and 3% choice white grease (HPDDG), or 30% DDGS with (3) no added fat (DDGS), (4) 3% choice white grease (DDGS + CWG), or (5) 3% butter oil (DDGS + BO). Postmortem carcass characteristics and quality attributes were not different between diets (P > 0.08) except the semimembranosus muscle from pigs fed HPDDGS had a more basic ultimate pH (P = 0.01) compared to all other treatments. Approximately 5x5 cm square fat samples were collected at the cranial tip of the jowl at the site of head removal, on the evisceration midline caudal to sternum, but anterior to mammary tissue, and the three quarter distance around the LM at the 10th rib. Subcutaneous back fat was separated into inner and outer layers. Intramuscular fat was collected via a composite sample of the 10th rib loin chop. Diet changed (P < 0.01) SFA, MUFA and PUFA in subcutaneous, intramuscular, belly and jowl fat depots. Both layers of subcutaneous fat and belly fat were the most saturated in pigs fed PCON diet (P < 0.01) and contained the greatest proportions of SFA and MUFA. Including 30% DDGS in the diet increased (P < 0.01) PUFA and decreased MUFA content in subcutaneous fat layers, jowl and belly fat. However, in IMF, 30% DDGS in the diet increased (P < 0.01) SFA and MUFA. Butter oil in the diet markedly increased (P < 0.01) CLA (18:9c11t isomer) in subcutaneous, jowl and belly fat. Although added fat in the diet altered fatty acid composition in multiple fat depots, adding additional saturated fat in the form of butter oil to the diet did not significantly improve other measures of carcass quality.

199 Comparative Analysis of the Porcine IGF2-G3072A Mutation and Reduced Myostatin Function on Carcass and Meat Quality Characteristics.

The objective of this study was to determine the relative effects of the porcine IGF2 mutation (IGF2-G3072A) and a novel, gene-editing derived myostatin loss-of-function (LOF) mutation on carcass traits and meat quality in pigs. The hypothesis was that both the IGF2 paternal A allele (Apat) and myostatin LOF mutation would increase muscle growth in pigs, but may potentially reduce loin and belly quality. Pigs were either IGF2 paternal G allele (Gpat) and wild-type (WT) for myostatin (n=13), Gpat and heterozygous (HET) for myostatin (n=10), Apat WT (n=11) or Apat HET (n=10). Pigs were raised in mixed sex pens of 10-15 pigs per pen, given free access to a diet that met or exceeded NRC nutrient requirements, and slaughtered at 175 d (±5 d) of age. Loin eye area and back fat depth was measured. Loin and belly quality was measured on the left side of the carcass. Warner-Bratzler shear force (WBSF) was used to determine tenderness of loin chops d14 postmortem. Data were analyzed using the MIXED procedure of SAS with a model including the effects of sex, IGF2, myostatin, and all interactions; means were separated using the pdiff option and considered different when P≤0.05. Ending live weight and hot carcass weight were similar among all genotypes (P≥0.05). Loin eye area was greater (P≤0.05) in HET pigs regardless of IGF2 genotype compared with WT pigs, and tended (P=0.10) to be greater in IGF2 Apat WT pigs compared with Gpat WT pigs. Back fat depth was similar (P≥0.05) among all genotypes. Longissimus dorsi (LD) muscle weighed less (P≤0.05) in WT Gpat pigs in comparison with all other genotypes, and was larger (P≤0.05) in Apat HET pigs compared with Apat WT pigs. Loins from myostatin HET pigs were paler than those from WT pigs, regardless of IGF2 genotype, as evidenced by an increased L* value of approximately 5 units (P< 0.01). However, L* of IGF2 Apat (52.1) and Gpat (53.9) pigs were similar (P≥0.05). Tenderness (WBSF) was similar (P≥0.05) among all genotypes. Bellies from IGF2 Gpat pigs were firmer as indicated by an increased (P<0.05) flop distance compared with all other genotypes. These data suggest that the partial loss of myostatin (HET) increased lean muscle deposition in pigs but resulted in poorer loin color. The IGF2 Apat mutation also tended to increase lean muscle deposition but did not negatively impact loin color. However, both mutations resulted in poorer belly firmness. The objective of this study was to determine the relative effects of the porcine IGF2 mutation (IGF2-G3072A) and a novel, gene-editing derived myostatin loss-of-function (LOF) mutation on carcass traits and meat quality in pigs. The hypothesis was that both the IGF2 paternal A allele (Apat) and myostatin LOF mutation would increase muscle growth in pigs, but may potentially reduce loin and belly quality. Pigs were either IGF2 paternal G allele (Gpat) and wild-type (WT) for myostatin (n=13), Gpat and heterozygous (HET) for myostatin (n=10), Apat WT (n=11) or Apat HET (n=10). Pigs were raised in mixed sex pens of 10-15 pigs per pen, given free access to a diet that met or exceeded NRC nutrient requirements, and slaughtered at 175 d (±5 d) of age. Loin eye area and back fat depth was measured. Loin and belly quality was measured on the left side of the carcass. Warner-Bratzler shear force (WBSF) was used to determine tenderness of loin chops d14 postmortem. Data were analyzed using the MIXED procedure of SAS with a model including the effects of sex, IGF2, myostatin, and all interactions; means were separated using the pdiff option and considered different when P≤0.05. Ending live weight and hot carcass weight were similar among all genotypes (P≥0.05). Loin eye area was greater (P≤0.05) in HET pigs regardless of IGF2 genotype compared with WT pigs, and tended (P=0.10) to be greater in IGF2 Apat WT pigs compared with Gpat WT pigs. Back fat depth was similar (P≥0.05) among all genotypes. Longissimus dorsi (LD) muscle weighed less (P≤0.05) in WT Gpat pigs in comparison with all other genotypes, and was larger (P≤0.05) in Apat HET pigs compared with Apat WT pigs. Loins from myostatin HET pigs were paler than those from WT pigs, regardless of IGF2 genotype, as evidenced by an increased L* value of approximately 5 units (P< 0.01). However, L* of IGF2 Apat (52.1) and Gpat (53.9) pigs were similar (P≥0.05). Tenderness (WBSF) was similar (P≥0.05) among all genotypes. Bellies from IGF2 Gpat pigs were firmer as indicated by an increased (P<0.05) flop distance compared with all other genotypes. These data suggest that the partial loss of myostatin (HET) increased lean muscle deposition in pigs but resulted in poorer loin color. The IGF2 Apat mutation also tended to increase lean muscle deposition but did not negatively impact loin color. However, both mutations resulted in poorer belly firmness.

Shelf-life and processing yields of moisture-enhanced pork loins formulated with “gourmet” salts

Objectives were to determine the effects of an industry-typical (Control) and 3 “gourmet” (Grey sea, Pink rock, and unrefined Rock) salts on the processing yields and shelf-life of moisture-enhanced pork loins. Loins (n = 41) were injected with a brine formulated to deliver 0.32 g/100 g of salt in the final product. Twelve loins were selected from each treatment to be cut into chops to undergo 6 d of retail display. Control-injected loins had greater (P ≤ .01) brine uptake and retention than loins injected with Pink or Rock brines, with Grey-injected loins being intermediate. Control-injected loin chops had reduced (P ≤ .02) reflectance ratio compared with all other treatments and were redder (P ≤ .02) than Grey- and Pink-injected chops. At 3, 4, 5, and 6 d of display, control-injected loin chops had greater (P ≤ .05) hue angle than all other treatments. There was no difference in visual discoloration among salt treatments until 4 d, at which point loin chops injected with control brine were more (P < .01) discolored than the other treatments throughout the remainder of the display period. These data suggest high purity salt improves brine retention, but may reduce color stability of moisture-enhanced pork loins.

Consumer Assessment of Lamb Loin and Leg from Australia, New Zealand, and United States

Lamb was sourced from 3 countries [Australia (AUS), New Zealand (NZ), and United States (US)] representing 2 muscle types (semimembranosus and longissimus lumborum) to evaluate the palatability of lamb loin and leg chops according to US consumers (n = 360). For tenderness, flavor, and overall liking, there was an interaction detected between source country and muscle (P &lt; 0.05). Overall, US loin chops had the highest (P &lt; 0.05) consumer sensory scores, were rated the most acceptable (P &lt; 0.05), and were placed in better than everyday quality or premium quality categories more often than all other treatments. Leg samples sourced from AUS and NZ were rated the lowest (P &lt; 0.05) for consumer sensory scores for tenderness, flavor liking and overall liking, as well as being the least acceptable (P &lt; 0.05) for flavor liking and overall liking. Both source country and muscle impacted (P &lt; 0.01) juiciness scores, as well as tenderness and juiciness acceptability. US chops were juicier and more acceptable for tenderness and juiciness than chops sourced from AUS or NZ, regardless of muscle; consumers rated loin chops juicier and more acceptable for tenderness and juiciness than legs chops, regardless of source country (P &lt; 0.05). Overall, consumers detected differences in palatability between muscle type and the source country. Loin chops were preferred over leg chops for all palatability traits. US consumers preferred the domestically sourced lamb over the lamb sourced from AUS and NZ; however, complete animal background (diet, gender, and age) and knowledge of potential differences in slaughter and chilling conditions, as well as control over postmortem aging, is needed to help differentiate if differences in flavor were due to diet, genetics, or other environmental factors.