Loin Chops Research Articles

Thermoforming Vacuum Packaging Influences Fresh Pork Loin Chop Characteristics.

The storage duration of fresh meat products is a contributing factor leading to increased waste and loss at the retail counter. Losses of fresh pork can be linked to packaging methods that do not protect the attributes of color, taste, and odors consumers use in determining wholesome meat. Boneless pork loins (N = 63) were fabricated into 2.54-cm-thick chops and assigned to one of three vacuum treatments (VacA, VacB, VacC) or a fourth polyvinyl chloride overwrap (PVC) treatment to assess objective fresh color, cook loss, Warner-Bratzler shear force (WBSF), and lipid oxidation. Pork chops (n = 882) were evaluated at 5-day intervals (D 0, 5, 10, 15) in a randomized complete block design. Pork chop surface color was lighter (L*; p < 0.0001) when stored in a vacuum compared to PVC-packaged loin chops, regardless of storage duration. Redness (a*) values were greater (p < 0.0001) for loin chops stored in PVC than all other vacuum packaging treatments throughout the entire 15-day display period. Relative values for chroma on PVC-packaged loin chops were greater (p < 0.0001) throughout the simulated retail display period. An interaction of day and packaging treatment (p < 0.0343) occurred for WBSF. Lipid oxidation for pork chops packaged using PVC was significantly greater (p < 0.0001) from Day 10 through the completion of the storage period. Results indicate that vacuum packaging limits the deterioration of fresh pork loin chops, whereas traditional overwrapping expedites the color and lipid oxidation during refrigerated storage.

Effects of maternal inflammation on growth performance, carcass characteristics, and meat quality of offspring pigs.

The objective of this research was to determine the effects of mid-gestational maternal inflammation on performance, carcass characteristics, and meat quality of offspring. Pregnant gilts were administered either lipopolysaccharide (LPS; n=7) or saline (CON, n=7) from d 70-84 of gestation. Gilts assigned to the LPS treatment were administered an intravenous injection of reconstituted LPS every other day with a beginning does of 10 μg LPS/kg BW and subsequent doses increasing by 12%, while CON gilts received intravenous injections of comparable volumes of saline. Gilts farrowed naturally, and at d 66 of age a total of 59 pigs, both barrows and gilts began a 3-phase feeding regimen designed to meet or exceed nutrient requirements for growing-finishing pigs. Pigs were weighed on d 0, 35, 70, and 105 of the finishing trial to determine ADG, ADFI, and G:F. On d 106, pigs were slaughtered under supervision of the United States department of Agriculture Food Safety Inspection Service (USDA-FSIS). Ending live weight (ELW), hot carcass weight (HCW), and dressing percentage were determined. Left side of carcasses were weighed and fabricated to determine carcass cutting yields. The semitendinosus was collected for histological samples. Fresh belly characteristics and loin quality were measured. Two chops were collected for Warner-Bratzler shear force (WBSF) and proximate analysis. No differences (P ≥ 0.13) between LPS and CON pigs were observed for growth performance in phases 1, 2, 3, or overall (d 0-105) performance with the exception of overall G:F reduced in CON pigs compared with LPS pigs (P = 0.03). There was a tendency for carcass yield to be reduced (P = 0.06; 0.82% units) in LPS pigs compared with CON pigs. Additionally, longissimus muscle area (LMA) tended to be reduced (P = 0.10) 2.27cm2 in LPS compared with CON pigs. Loin chop quality traits including instrumental color, subjective color, marbling, firmness, pH, and drip loss were not different (P ≥ 0.09) between LPS and CON pigs. Fresh belly characteristics were not different (P ≥ 0.22) between LPS and CON pigs. There were no differences in primal and subprimal weights, except for LPS pigs tended to have a reduction (P ≥ 0.07) in tenderloin and Canadian back weights compared with CON pigs. Furthermore, LPS pigs had no differences (P ≥ 0.25) in muscle fiber composition or size, however LPS pigs tended (P = 0.10) to have a 13% reduction in estimated muscle fibers number compared with CON pigs. In summary, mid gestational inflammation did not result in reduced meat quality, growth performance, or carcass yields of offspring.

128 Effects of dietary hybrid rye on quality and consumer acceptability of pork from pigs raised under organic conditions

Abstract In organic pig production, hybrid rye grain and straw can be used as feed and bedding, respectively, to reduce production costs. However, there is a concern that replacing corn with hybrid rye in pig diets may affect pork quality. In this study, we investigated whether inclusion of hybrid rye in pig diets can affect quality and consumer acceptability of pork from organically raised pigs. Pigs [n = 200, initial body weight (BW) = 26.8±3.5 kg, 10 wk of age] were assigned to Control or Rye treatments (50 pigs/pen; 2 pens/treatment) within a hoop barn and stratified for BW and sex across pens. Control pigs received corn, soybean meal-based diets. Rye pigs were fed diets in which hybrid rye replaced 50% of the corn in control diets. Near market BW (average = 127 kg, 22 wk of age), 8 pigs per pen (4 barrows and 4 gilts) closest to the average BW of all pigs in the pen were selected for evaluation of pork quality and consumer acceptability. Carcass pH at 45 min and 24 h postmortem in the ham, and objective color scores (L*, a*, b*), shear force, and subjective color and marbling scores were collected from a loin chop. Loin chops were kept at or below -18°C until a consumer taste panel was conducted to assess overall liking, flavor liking, texture liking, toughness, juiciness, and off-flavor of pork from the cooked loin chops. Liking ratings were made on 120-point scales (0 - strongest dislike imaginable, 120 - strongest like imaginable). Toughness, juiciness, and off-flavor were ranked on 20-point scales (0 - none, 20 - extremely tough, juicy, or intense, respectively). Data were analyzed using the Mixed procedure, Frequency procedure with chi-square test of SAS. Measures of pork quality (pH at 45 min and 24 h, a*, b*, shear force, and subjective marbling and color scores) were not different between treatments (Table 1). Pigs fed Control diets displayed a greater (P = 0.006) L* reading than Rye-fed pigs indicating that pork from Control pigs was lighter in color than Rye-fed pigs. Generally, the taste panel did not detect a difference in acceptability of pork from Control and Rye-fed pigs. Juiciness and off flavor were scored very similarly by panelists. However, pork from Rye-fed pigs tended (P = 0.075) to be tougher than pork from Control pigs. Liking attributes (overall liking, flavor liking, and texture liking) were scored similarly between Rye-fed and Control pigs and generally better than neutral (neutral=60/120) by panelists. These data suggest that replacing 50% of corn with hybrid rye in diets for growing-finishing pigs will not negatively impact quality or consumer acceptability of pork.

133 The effect of sire lines and endpoint cooking temperature on consumer eating experience and visual appeal in pork loin chops

Abstract Prior research and public perception of pork suggest breed influence visual characteristics like color and size and palatability traits like tenderness and flavor of pork chops. Therefore, the objective of this study was to assess consumer perception of visual appeal and palatability of pork loin chops from three sire lines cooked to two different degrees of doneness (DOD). Boneless pork loins from three sire lines (Duroc, Berkshire, and Synthetic) were aged to 14 d post-mortem. Loin quality was then measured, and 2.54-cm chops were frozen from each loin. Chops from each sire line were overwrap-packaged in sets of two and displayed in a retail case with two representative packages per sire line. Panelists rated each package for color, marbling, and size on a just about right (JAR) scale and then indicated their overall liking of each package. Chops from each sire line were cooked to either 63°C or 71°C, cut into 1-cm cubes and two samples from each chop were served to each consumer. Panelists rated 6 samples, each sire line and DOD, for tenderness, flavor, and juiciness on a JAR scale and then rated overall liking. Data were analyzed as a randomized complete block design (RCBD) in SAS 9.4 with panelist age range serving as an influence effect for all panel data. Berkshire chops did not differ (P &amp;gt; 0.08) in redness from other chops, but required 0.13 kg less force to shear, and had a 16.23 cm2 smaller LEA compared with Synthetic and Duroc chops (P &amp;lt; 0.02). Duroc chops had the greatest marbling (P &amp;lt; 0.04) but did not differ in visual color score from other treatments (P &amp;gt; 0.10). There were no differences in consumer visual evaluations (P &amp;gt; 0.45), with traits from all sire lines averaging between 43 and 57 (JAR = 50). Sire line also did not alter visual liking (P = 0.94). There were tendencies for interactions (P &amp;gt; 0.09) between DOD and sire line for consumer sensory evaluation. In general, consumers rated Berkshire chops cooked to 63°C more favorably than other sire line and DOD combinations. Consumers rated chops with different DOD similarly for tenderness and flavor, but tended to score juiciness of chops cooked to 63°C closer to JAR (P = 0.07). Duroc chops were the least tender and least acceptable (P &amp;lt; 0.05). Berkshire chops were juicer than Duroc and Synthetic chops (P &amp;lt; 0.02). Overall, consumers scored all chops between 3.1 and 12.3 units below the JAR line (100-unit scale) regardless of sire line or DOD for tenderness, juiciness, and flavor with overall acceptability within 10 units of neither like nor dislike, which may be indicative of consumers general negative perceptions of pork loin chops.

USA millennial and non-millennial beef consumers perception of beef, pork, and chicken

Millennials have been shown to have distinctly different behaviors; however, factors affecting their liking of beef, pork and chicken has not been fully elucidated. As millennials are current and future animal protein consumers, the question of if they have different drivers of liking for beef, pork, and chicken has not been answered. Top loin steaks cooked to 58.3 or 80 °C; and pork loin chops and chicken breasts cooked to 62.7 or 80 °C were cooked on a flat grill. Beef bottom round roasts cooked to 58.3 or 80°; and pork inside ham roasts and chicken thighs were cooked to 62.7 or 80 °C in a Crock-pot®. A descriptive flavor and texture attribute panel and a consumer central location test in four cities were used to evaluated flavor and texture attributes. Consumers were either millennials or non-millennials, and light or heavy beef-eaters. Meat descriptive flavor and texture attributes differed by cooking method, cut, and internal temperature (P < 0.05). Consumers preferred grilled meat more than meat cooked in the Crock-pot® (P > 0.05). Consumers rated grill flavor, juiciness, and tenderness (P ≥ 0.05) higher in grilled meat. Light beef-eaters, those who ate beef 2 to 4 times per month, rated overall, flavor, and species flavor lower (P < 0.05) than heavy beef-eaters, but consumers liked beef regardless of generational segment or their consumption of beef; however, millennials rated overall, overall flavor, and tenderness liking slightly lower than non-millennials. These results indicate that millennials have similar drivers of liking as non-millennials across beef, pork, and chicken protein sources.

Sensory and volatile aromatic compound differences of paired lamb loins with 0 or 14 day dry aging

Flavor of lamb is a major driving factor in eating satisfaction. Dry aging has been used in beef to alter flavor and tenderness. The objective of the research was to determine what affect dry aging had on flavor attributes and the volatile compounds that influence the perception of flavor. Lambs (n = 10) were fed an alfalfa-based concentrate diet for 60 d prior to harvest. Loins were obtained from both sides of the carcass and randomly assigned to an aging treatment; no age (boned and frozen day 0) or 14 d of dry age in cold storage (4°C, 55%RH). Descriptive flavor profile panel evaluated samples and volatile compounds were analyzed from cooked samples. No differences were detected by descriptive flavor panel between fresh and dry aged loin chops for most flavor attributes. However, aged loins were rated saltier than loins not aged. Additionally, aged loin chops tended to have a greater intensity score for mutton and green attributes. Aldehydes were the greatest proportion of the volatile aroma compound chemical classification recovered and identified from the lamb samples. Dry-aged lamb loins yielded greater thiobis-methane (a sulfurous, fishy aroma) than loins without ageing. As expected, muscle fiber tenderness as evaluated by sensory panel was greater for aged loin chops than no age (12.7 and 10.0, respectively). Aged loin chops tended to be juicier as well. Aging in aerobic conditions for up to 14 d can improve tenderness in lamb without significantly impacting flavor, however, there is a tendency to increase the mutton and green flavors with dry aging.

Carcass and meat quality characteristics of purebred (hair) and crossbred (wool × hair) sheep lambs grazing fescue pasture as influenced by breed type, sex, and supplementation

ABSTRACT The influence of breed type (purebred vs. crossbred), sex (short-scrotum ram vs. ewe lamb), and supplementation (pasture-only vs. pasture plus 2% soy hull) on carcass and meat quality of landrace hair (Barbados Blackbelly; BB and St. Croix; SX) and wool (Dorset; DO) × hair sheep lambs was evaluated. Forty-eight, mixed sex 5-mo old purebred hair (body weight (BW) = 17.9 ± 1.95 kg) and crossbred (wool × hair) sheep lambs (BW = 21.7 ± 2.56 kg) rationally grazed predominantly tall fescue pasture during summer with or without soy hull supplementation at 2% of BW. At the end of a 90-d grazing trial, lambs were harvested using the USDA standard procedures and their carcasses were evaluated. After 24 h chilling storge (2°C), longissimus muscle (LM) pH was measured, and carcasses were fabricated into primal cuts. Loin chops and fat depots were collected to analyse meat quality parameters. Supplementation rather than crossbreeding had more significant effect on carcass quality under the conditions of this experiment. Regardless of breed type, soy hull supplementation improved colour, lipid oxidation stability and texture properties of fresh lamb, whereas pasture-only lambs had healthier fatty acid profiles compared with those from supplemented lambs.

414 Awardee Talk: Current Status and Future Opportunities for Fresh Pork Quality

Abstract Pork is often viewed as a “middle-of-the-road” option. It is typically less expensive than beef, but more expensive than chicken. While beef cuts, especially steaks, are viewed as luxury items or high-end dining experiences, pork is more of a staple food featured as a variety of fresh and processed products at breakfast, lunch, and dinner. To increase demand for pork and capture more of the high-end market, improving fresh pork loin quality has been a focus of the industry for many years. There is evidence that these efforts have been successful. Compared with pork of the past, fresh pork loins have increased pH and darker color. Additionally, the incidence of tough pork has been reduced and overall pork tenderness improved. However, per capita consumption of pork by the consumers of the United States has not changed. This suggests that consumer acceptance and demand for fresh pork may not depend on intrinsic characteristics such as pH, color, and tenderness. Extrinsic factors like endpoint cooking temperature may have a larger influence on consumer acceptability of fresh pork loin chops. It is possible that, in terms of pork quality, we have been successful in eliminating the problems of the pork industry like pale, soft and exudative pork, but this is not sufficient to reach a consistently excellent eating experience in pork loins.

68 Impact of Increasing Levels of Hybrid Rye on Carcass Characteristics and Product Sensory Evaluation in Grow-Finish Pigs

Abstract The objective of this trial was to determine the effects of hybrid rye (KWS Bono) inclusion rate on lean muscle deposition and product quality of grow-finish pigs. A total of 2,400 barrows and gilts (FAST x PIC 800, 44.9 kg) were randomly allotted to 1 of 4 dietary treatments. Diets were corn-soybean based with hybrid rye replacing either 0, 40, 70 or 100% of the corn in the diet. All diets were formulated to meet or exceed the 2012 NRC requirements for all nutrients, and a five-phase feeding program was utilized (44.9 to 56.0, 56.0 to 69.0, 69.0 to 87.9, 87.9 to 107.5, and 107.5 to 111.6 kg). Pigs were weighed and feed disappearance measured at each phase change. Pigs were marketed across three events and (%) Yield, Hot Carcass Weight (HCW), Backfat (BF) and Iodine Value (IV) were measured at the procurement facility. Two primal sections (loins and bellies) were removed from 88 pigs (22/treatment) and sent to the KSU Meat Lab Facility to be cooked or smoked for a trained, sensory panel evaluation. Data were analyzed using the GLIMMIX procedure of SAS, with block as a random effect and pre-planned linear and quadratic contrast statements to analyze the inclusion of hybrid rye. Results indicate that increasing hybrid rye inclusion rate from 0 to 100% decreased (P &amp;lt; 0.001) average market BW, % Yield, HCW, BF and IV all decreased (P &amp;lt; 0.001) as hybrid rye inclusion rate increased (Table 1). The sensory measures for loin chops for Initial Juiciness, Sustained Juiciness, Myofibrillar Tenderness and Overall Tenderness decreased (P &amp;lt; 0.05) with increasing hybrid rye. Connective Tissue Amount, Pork-Flavor Intensity and Off-Flavor Intensity were not affected (P &amp;gt; 0.10) by dietary treatment. All bacon measures including Texture, Saltiness, Smoke Intensity, Bacon Flavor and Off Flavor were not affected by hybrid rye inclusion (P &amp;gt; 0.10). In summary, while there was a reduction in HCW, BF, % Yield, IV and certain sensory values for loins as hybrid rye increased, there was no effect on any of the bacon variables measured. Therefore, depending on economics, hybrid rye can be an acceptable replacement for corn in finishing pig diets.

Performance of a Handheld Near-Infrared Spectroscopy Device to Predict Pork Primal Belly Fat Iodine Value and Loin Lean Intramuscular Fat Content.

The increase in market demand and economic value of Canadian pork primal cuts has led to a need to assess advanced technologies capable of measuring quality traits. Fat and lean composition were measured using a Tellspec near-infrared (NIR) spectroscopy device to predict the pork belly fat iodine value (IV) and loin lean intramuscular fat (IMF) content in 158 pork belly primals and 419 loin chops. The calibration model revealed a 90.6% and 88.9% accuracy for the Tellspec NIR to predict saturated fatty acids (SFA) and IV, respectively, in the belly fat. The calibration model accuracy for the other belly fatty acids revealed an accuracy of 66.3-86.1%. Using the Tellspec NIR to predict loin lean IMF reported a lower accuracy for moisture (R2 = 60) and fat % (R2 = 40.4). This suggests that Tellspec NIR spectroscopy measures on the pork belly primal offers a cost-efficient, rapid, accurate, and non-invasive indicator of pork belly IV and could be used for the classification for specific markets.

Evaluation of growth, meat quality, and sensory characteristics of wool, hair, and composite lambs.

The objectives of this study were to evaluate the growth rates, carcass quality, shelf-life, tenderness, sensory characteristics, volatile compounds, and fatty acid composition of wool, hair, and composite (wool × hair) lambs. Twenty-one wether lambs [wool (Suffolk × Polypay/Targhee; n = 7), hair (Dorper × Dorper; n = 7), and composite (Dorper × Polypay/Targhee; n = 7)] were fed from weaning to finishing at the University of Idaho Sheep Center and subsequently harvested under United States Department of Agriculture inspection at the University of Idaho Meat Lab. At 48 h postmortem, carcass measurements were taken to determine the percent boneless closely trimmed retail cuts, yield grade, and quality grade. Loins were fabricated from each carcass and wet-aged at 0°C until 10-d postmortem. Following aging, 2.54-cm bone-in loin chops were cut and randomly assigned to 4 d of retail display, Warner-Bratzler Shear Force (WBSF), or sensory analyses. Thiobarbituric acid reactive substances were analyzed on days 0 and 4 of retail display while subjective and objective color measurements were observed once daily. Samples (24 g) were also collected for volatile compound and fatty acid analysis. A mixed model analysis of variance was used to assess breed differences. Discernable effects were considered at P < 0.05. Wool lambs had heavier hot carcass weights (P < 0.001), larger rib-eye area (P = 0.015), and higher dressing percent (P < 0.001) than the other breeds. There was an interaction observed between breed and days of retail display for browning (P = 0.006). On day 1 chops from the composite breed had more browning than chops from the wool breed. No differences were observed between groups for lean muscle L* values (P = 0.432), a* values (P = 0.757), and b* values (P = 0.615). Differences were not observed in lipid oxidation (P = 0.159), WBSF (P = 0.540), or consumer acceptability (P = 0.295). There were differences found for 7 of the 45 fatty acids detected and in 3 of the 67 volatile compounds detected. In conclusion, wool lambs were heavier and had a greater carcass yield than the hair lamb carcasses. Regardless of breed, consumers did not detect sensory traits that would impact their eating experience.

Intake, growth performance, carcass traits, and meat quality of feedlot lambs fed novel anthocyanin-rich corn cobs.

Feeding anthocyanin- and antioxidant-rich forages to sheep and dairy cows can improve performance and product quality. The objective of this study was to evaluate the impact of feeding anthocyanin-rich (Hi-A) corn cobs on the growth performance and meat quality of lambs. A total of 30 eight-month-old Rambouillet ewe lambs (body weight 30.7 ± 1.2 kg) were fed for 63 days with three diets consisting of 80% concentrate and 20% roughage: Hi-A corn cobs (Hi-A), regular corn cobs (Low-A), and bermudagrass hay (BGH). A completely randomized design trial with 10 lambs per treatment was used. Data were collected on dry matter intake (DMI), body weight (BW), average daily gain (ADG), gain:feed ratio (G:F), carcass traits, meat color, fatty acid (FA) profile, volatile aroma compounds, and sensory panels. After feeding for 63 days, lambs were harvested, and the carcasses were evaluated. Boneless lamb loin chops were fabricated and submitted to FA, aroma, and sensory analysis. The corn cob diets did not affect BW, ADG, or G:F of the lambs compared to BGH diet, but DMI (P < 0.01) was decreased. The dressing percentage was greater (P < 0.05) in lambs fed BGH than in those fed Hi-A, while lambs fed Low-A did not differ from the other two diets. Loin chop instrumental color characteristics were not influenced by diets, except the hue angle, which was greater (P < 0.05) in lambs fed Hi-A than Low-A, while BGH did not differ from lambs fed either cob diet. There was no significant difference in the meat fatty acid profile. Five volatile compounds were affected by diets. The 2-butanone (P = 0.07) and 2,3-butanedione (P = 0.05) were greater in chops from lambs fed BGH relative to lambs fed Hi-A and neither differed (P > 0.05) from lambs fed Low-A diet. The 2-propanone was greater (P = 0.01) in chops from lambs fed BGH than in those fed either the Low-A or Hi-A diets. Both 3-methyl-butanal and methyl benzene were lower (P = 0.01 and P = 0.02, respectively) in chops from lambs fed the Hi-A diet than in those fed either the BGH or Low-A diet. Replacing 20% bermudagrass hay with corn cobs in the diets of feedlot lambs did not affect sheep growth performance, meat fatty acid profile, sensory traits, and most carcass characteristics and meat color parameters. Hi-A corn diet improved aroma in cooked boneless loin chops, but sensory traits were not affected. This study showed the Hi-A corn cobs can be safely used for roughage and feed for lambs and for improving meat aroma in cooked boneless loin chops.

RNA-Seq exploration of the influence of stress on meat quality in Spanish goats

Studies exploring the transcriptome of stress and its effects on meat quality are very limited, particularly in goats. Fifty-four male Spanish goats (8-mo old; BW = 29.7 ± 2.03 kg) were randomly subjected to one of three treatments (TRT; n = 18 goats/treatment): (1) transported for 180 min, (2) transported for 30 min, or (3) held in pens (control) to analyze the transcriptome of stress and meat quality in goats using RNA-seq technology. Blood samples were collected before and after treatment, and meat samples were collected after humane slaughter for stress hormone, meat quality (Longissimus dorsi), and transcriptomic analysis. Plasma epinephrine concentrations were higher (P < 0.01) in 180 min and 30 min groups compared to the control group; however, norepinephrine concentrations were not affected by the treatment. Muscle glycogen concentrations (15 min postmortem) were lower (P < 0.01) in both 30 min and 180 min groups compared to the control group. Calpastatin levels were higher (P < 0.01) in 180 min and 30 min groups than the control group. Warner–Bratzler shear force values of loin chops were the highest in the 180 min group (4 ± 0.15, kg), lowest in the control group (3.51 ± 0.10, kg), and intermediate in the 30 min group (3.78 ± 0.09, kg; P < 0.01) both at day 1 and day 6 aging time. Additionally, desmin levels of day 6 samples were lowest in the control group, highest in 180 min group, and intermediate in 30 min group (P < 0.05). RNA-seq results showed that a total of 10,633 genes were differentially expressed (5194 up regulated; 5439 down regulated) among all comparisons (blood and day 1 and day 6 muscle samples). Among these differentially expressed genes (DEGs), KLF9, AMPK, FOXO3, PTX3, GADD45, PTPN1, CASP7, MAPK4, HSPA12A, and JAK-STAT were probably associated with the effects of stress on skeletal muscle proteins and involved in biological process such as cellular response to corticosteroid stimulus, endoplasmic reticulum stress, insulin resistance, DNA repair, apoptosis, MAPK cascade and regulation of proteolysis. The KEGG analysis revealed that AMPK and JAK-SAT signaling pathways and autophagy were among the top 20 enriched pathways in our treatment comparisons. The results provide an understanding of the genes and pathways involved in stress responses and related changes in postmortem muscle metabolism and meat quality characteristics in goats.

Characterization of Pork Loin Chop Color Stability Using Loin Quality Traits and Instrumental Discoloration Measures

The objective of this study was to characterize the color stability of pork loin chops using fresh quality traits and instrumental measures of discoloration. Boneless pork loins (N=484) were evaluated for quality traits at 11 or 14 d post-mortem. One chop was cut from each loin near the 10th rib for retail display, overwrapped, and displayed under constant fluorescent lighting for 7 d. Objective color, myoglobin redox forms, and subjective visual discoloration traits were evaluated daily. After retail display, chops were categorized based on final visual discoloration (Day 7) as Very Color Stable (VCS; 0% to 5% discoloration), Color Stable (CS; 5% to 10% discoloration), Neutral (10% to 25% discoloration), Color Labile (CL; 25% to 30% discoloration), or Very Color Labile (VCL; &amp;gt;30% discoloration). Quality and color traits were analyzed using the GLIMMIX (visual discoloration) or MIXED (all other measures) procedure of SAS. Retail display data were analyzed as repeated measures. Chops ultimately classified as CS or VCS were darker, redder, and had lesser surface metmyoglobin (P&amp;lt;0.01) than CL and VCL chops at both Day 1 of retail display and throughout display. Stable chops also had generally increased R630/580 values as well as decreased visual discoloration scores and yellowness during display. A group×day interaction was observed for all traits measured during retail display (P&amp;lt;0.0001). No differences in aged loin ventral surface redness were observed between color stability groups (P≥0.16). Overall, chops ultimately classified as CS came from aged loins that were generally darker, redder, and less yellow, with greater pH values, greater marbling scores,and decreased purge loss.

PSIII-A-1 Acute Stress Effects on Physiological Responses and Meat Quality Changes in Goats

Abstract Duration of stress prior to processing can significantly affect physiological status and meat quality in goats. This experiment was conducted to determine the effects of duration of preslaughter stress on physiological responses and meat quality in goats. In a Randomized Complete Block Design, fifty-four uncastrated male Spanish goats (8-mo old; BW 29.7 ± 2.03 kg) were randomly subjected to one of three treatments (n = 18 goats/treatment): (i) transported for 3 h, (ii) transported for 30 min, or (iii) or held in pens (control) on two different days. Blood samples were collected before and after transport for assessment of stress responses. Goats were slaughtered, using humane procedures, for meat quality analysis. The data were analyzed using MIXED procedures in SAS with treatment and day as fixed variables. Cortisol concentrations were higher (P &amp;lt; 0.01) in both 3 h (117.7 ± 7.96 ng/mL) and 30 min (130.1 ± 8.05 ng/mL) transported groups compared to the control group (27.5 ± 7.59 ng/mL). A similar treatment effect was noticed in plasma non-esterified fatty acid (P &amp;lt; 0.05) concentrations. Glucose concentrations were highest in 180-min, lowest in control, and intermediate in 30-min group (P &amp;lt; 0.01). There were significant positive correlations among muscle desmin concentration after 6 days of aging and 24 h pH (P &amp;lt; 0.05) and calpastatin activity (P &amp;lt; 0.05), suggesting that desmin degradation plays a role in determining the tenderness of aged meat from goats subjected to preslaughter stress. Warner-Bratzler shear force values of loin chops were highest in 180-min, lowest in control, and intermediate in 30-min groups; however, treatment did not influence the color values or cooking loss of loin chops. The results indicate that acute stress prior to processing can affect both physiological responses and meat quality in a duration-dependent manner in goats.

Effects of feeding high oleic soybean oil to growing-finishing pigs on loin and belly quality.

Feeding growing-finishing pigs supplemental fat is a common practice in the swine industry and can result in improved feed efficiency and reduced feed intake; however, dietary lipids also play a key role in determining pork quality. Objectives of the study were to evaluate the effects of feeding graded levels of high oleic soybean oil (HOSO) on loin and belly quality. A total of 288 pig raised in two separate blocks (144 pigs each) were assigned to one of four diets containing either 25% dried distiller's grains with solubles (DDGS), 2% high oleic soybean oil (HOSO2), 4% high oleic soybean oil (HOSO4), or 6% high oleic soybean oil (HOSO6). Following the conclusion of the feeding trial, 144 pigs were slaughtered at the University of Illinois Meat Science Laboratory. Following fabrication, loins were collected for the evaluation of fresh quality measurements and color stability. Belly quality and fatty acid composition were evaluated using skin-on natural fall bellies. There were no differences (P ≥ 0.11) in pH, visual color, lightness (L*), drip loss, or WBSF among dietary treatments. However, visual marbling was increased (P ≤ 0.01) in loin chops from pigs fed HOSO4 and HOSO6 treatments compared with chops from pigs fed the DDGS dietary treatment. Additionally, loin chops were more red (a*) (P ≤ 0.01) from pigs fed HOSO diets when compared with pigs fed DDGS. Extractable lipid was decreased (P ≤ 0.01) in fresh loin chops from pigs fed DDGS and HOSO2 diets compared with pigs fed HOSO6. There were no differences (P ≥ 0.75) in trained sensory tenderness, juiciness, or flavor for loin chops from pigs fed different dietary treatments. Pork fatty acid composition was altered by dietary HOSO inclusion, with pigs fed DDGS having (P ≤ 0.01) the greatest concentration of C16:0 and was decreased with increasing levels of HOSO inclusion. Inversely, the percentage of C18:1n-9 was least (P ≤ 0.01) in pigs fed DDGS and increased with increasing levels of HOSO inclusion. Pigs fed DDGS produced wider (P ≤ 0.03) and thinner (P ≤ 0.04) bellies with reduced flop distance compared with pigs fed HOSO diets. Overall, HOSO diets did not negatively affect fresh loin quality or sensory traits of loin chops. Furthermore, feeding HOSO to swine resulted in bellies containing greater percentages of oleic acid and reduced percentages of palmitic and linoleic acid.

Differences in carcass chilling rate underlie differences in sensory traits of pork chops from pigs with heavier carcass weights.

Pork hot carcass weights (HCW) have been increasing 0.6 kg per year, and if they continue to increase at this rate, they are projected to reach an average weight of 118 kg by the year 2050. This projection in weight is a concern for pork packers and processors given the challenges in product quality from heavier carcasses of broiler chickens. However, previous work demonstrated that pork chops from heavier carcasses were more tender than those from lighter carcasses. Therefore, the objective was to determine the effects of pork hot carcass weights, ranging from 90 to 145 kg with an average of 119 kg, on slice shear force and sensory traits of Longissimus dorsi chops when cooked to 63 or 71 °C, and to assess if differences in chilling rate can explain differences in sensory traits. Carcasses were categorized retrospectively into fast, medium, or slow chilling-rates based on their chilling rate during the first 17 h postmortem. Loin chops cut from 95 boneless loins were cooked to either 63 or 71 °C and evaluated for slice shear force and trained sensory panel traits (tenderness, juiciness, and flavor) using two different research laboratories. Slopes of regression lines and coefficients of determination between HCW and sensory traits were calculated using the REG procedure in SAS and considered different from 0 at P ≤ 0.05. As hot carcass weight increased, chops became more tender as evidenced by a decrease in SSF (63 °C β = -0.0412, P = 0.01; 71 °C β = -0.1005, P < 0.001). Furthermore, HCW explained 25% (R2 = 0.2536) of the variation in chilling rate during the first 5 h of chilling and 32% (R2 = 0.3205) of the variation in chilling rate from 5 to 13 h postmortem. Slow- and medium-rate chilling carcasses were approximately 12 kg heavier (P < 0.05) than fast chilling carcasses. Slice shear force of chops cooked to 63 and 71 °C was reduced in slow and medium chilling compared with fast chilling carcasses. Carcass temperature at 5 h postmortem explained the greatest portion of variation (R2 = 0.071) in slice shear force of chops cooked to 63 °C. These results suggest that carcasses tend to chill slower as weight increases, which resulted in slight improvements in sensory traits of boneless pork chops regardless of final degree of doneness cooking temperature.

Muscle Fatty Acids, Meat Flavor Compounds and Sensory Characteristics of Xiangxi Yellow Cattle in Comparison to Aberdeen Angus.

Simple SummaryWith agricultural mechanization and the increasing demand for meat, Xiangxi yellow cattle are increasingly being raised for meat production. Little is known about the changes in muscle composition and eating quality of the cattle at different ages. In the present study, the muscle proximate composition, meat flavor substances, and sensory quality of Xiangxi yellow cattle at different growth stages were profiled in comparison to Aberdeen Angus cattle, which may provide valuable information for high grade beef production from Xiangxi yellow cattle. This study showed that Xiangxi yellow cattle is a fine cattle breed with equal or even better meat quality attributes when compared to Angus. It is proper to slaughter Xiangxi yellow cattle at the age of 18 months for high quality beef production.The objective of this study was to investigate meat quality of Xiangxi yellow cattle of different ages in comparison to Aberdeen Angus. At the ages of 6, 18, and 30 months, 10 female animals for both Xiangxi yellow cattle and Aberdeen Angus cattle were randomly selected and slaughtered. The proximate composition analysis, fatty acid profiles and flavor compounds were measured on the longissimus thoracis (LT) muscle samples. One boneless loin chop was dissected and used for sensory evaluation by a 10-persoon trained taste panel. The data obtained showed that Xiangxi yellow cattle deposited similarly high level of intramuscular fat as Angus at the age of 18 month and the polyunsaturated fatty acid in muscle along with the PUFA/SFA ratio reached the highest levels at this age. Inosine 5′-monophosphate (IMP) was the predominant umami compound in beef, which concentration was significantly higher (p < 0.05) at month 18, but not different between Angus and Xiangxi yellow cattle. Multiple volatile flavor compounds were higher (p < 0.05) in concentrations in meat from Xiangxi yellow cattle at ages of 18 and 30 months when compared to Angus. Sensory analysis revealed that Xiangxi yellow cattle (18 and 30 months) and Angus (30 months) were superior in meat overall eating quality to Xiangxi yellow cattle (6 months) and Angus (6 and 18 months). This study showed that Xiangxi yellow cattle are a fine cattle breed with equal or even better meat quality attributes when compared to Angus. It is proper to slaughter Xiangxi yellow cattle at the age of 18 months for high quality beef production.

84 Carcass Characteristics, Meat Color and Fatty Acid Profile of Feedlot Lambs Fed Novel Anthocyanin-rich Corn Cobs

Abstract Hi-A™ is a unique type of corn developed by Texas A&amp;M AgriLife that has high anthocyanin. A completely randomized design trial was used to evaluate the effects of three roughages, Hi-A™ corn cobs, low-A (regular) corn cobs and bermudagrass hay (BGH), in feedlot Rambouillet ewe lamb (n = 10/treatment) diets on carcass characteristics, meat color and fatty acids (FA) profile. Lambs were fed experimental diets (20% roughage and 80% concentrate) for 63-d. Then, lambs were harvested, and the carcasses evaluated. Boneless lamb loin chops, 2.5 cm thick, were fabricated and analyzed for color and FA. Data were analyzed by ANOVA for a completely randomized design with diet as fixed effects and animal as a random effect with an alpha of 0.05. Carcass weight, loin eye area (LEA), body wall thickness, fat thickness, leg score, marbling, skeletal maturity, lean maturity, and flank streaking did not differ among treatments (P &amp;gt; 0.05). Dressing percentage was greater (P &amp;lt; 0.05) in the lambs fed BGH compared to Hi-A™ diets; neither of which differed (P &amp;gt; 0.05) from lambs fed Low-A. Instrumental color characteristics L* (darkness to lightness), a* (redness), b* (yellowness) and chroma (total color) of fresh lamb loin chops measured under retail display did not vary (P &amp;gt; 0.05) among treatments. Hue Angle (discoloration) was greater (P &amp;lt; 0.05) in loin chops from lambs fed Hi-A™ than Low-A diets, while BGH did not differ (P &amp;gt; 0.05) from the other treatments. Retail display day influenced (P &amp;lt; 0.05) all the instrumental color characteristics, with the highest values of L*, a*, b*, and chroma on day 1 and Hue Angle on days 3 and 4. No differences (P &amp;gt; 0.05) were observed in the meat FA profile. No advantages of using Hi-A™ corn cobs in feedlot lamb diets were observed regarding carcass characteristics, meat color and FA profile.

Consumer evaluation of meat quality from barrows, immunocastrates and boars in six countries

The practice of surgical castration of piglets and its alternatives is still under debate. Production of boars may impair meat quality due to boar taint and reduced tenderness compared to meat from surgically castrated male pigs, while immunocastration reduces boar taint and may improve meat quality but seems to be less accepted by the pig chain. In this study, we aimed to evaluate the consumer’s sensory appreciation of meat from barrows (BAs), immunocastrates (ICs) and boars (BOs) in six European countries, taking into account the selection of tainted carcass and consumers’ appreciation of boar taint. Loin chops of 30 BAs, 30 ICs and 30 BOs were evaluated by 752 consumers in six countries: Belgium, Czech Republic, Poland, Portugal, Romania and Spain. Consumers rated odour, flavour, tenderness, juiciness, overall liking and willingness to buy and sensitivity to and liking of androstenone (AND) and liking of skatole (SKA) was also tested. In each of the six countries, consumers liked the odour of the BO samples less than that of BA, and IC intermediate. For flavour, tenderness, juiciness, overall liking and willingness to buy, liking scores given by the Czech, Polish and Portuguese consumers significantly differed between the BA, BO and IC. Willingness to buy was highest for BA by Czech and Polish consumers and for BA and IC by Portuguese consumers. The frequency of the negative check all terms that apply terms also differed, with a higher frequency of disgusting for BO compared to BA and IC and of off-flavour, irritating, manure, sweat, disappointing compared to BA, and intermediate for IC. 31% of the consumers disliked the odour of AND (NEGAND), and 36% of them were not sensitive; in contrast, 77% of the consumers disliked SKA (NEGSKA). The decrease in flavour liking score for BO compared to BA and IC was more outspoken by the NEGAND consumer, while NEGSKA consumers gave an overall lower liking score independent of the type of male pig. The results of this study indicate that IC can be a valid alternative for surgical castration.