Boneless Chops Research Articles

41 Characterizing the amount and variability of intramuscular fat deposition throughout the loin using barrows and gilts from two genotypes

Abstract Pork quality is evaluated by commercial processors along the ventral surface of whole boneless loins. However, in retail settings boneless chops are evaluated individually for quality. The objective was to determine the variability in marbling attributable to chop location, sex, and sire line. The population of pigs evaluated were sired by commercial duroc boars selected for meat quality (MQ; n=96) or lean growth (LG; n=96) and equally split between sexes. Upon slaughter and fabrication, bone-in chops were removed from four locations along the loin (A=6th rib, B=10th rib, C=last rib, D=4th lumbar). Pairs of chops from each location were used for visual color, visual marbling, and subjective firmness, Warner-Bratzler shear force, and determination of moisture and extractable lipid (IMF). Variability across location, sex, and sire line was measured using a Levene’s test and the VARCOMP procedure of SAS was used to evaluate the proportion of variability each contributed to total variance. Barrows produced chops with greater IMF (3.64%) and variability (P< 0.001) than gilts (3.20%; P< 0.001). Chops from MQ pigs exhibited greater IMF (4.02%) and variability (P< 0.001) than LG (2.82%; P< 0.001). Chops from location A (3.80%) and D (3.77%) had greater IMF than B (3.34%; P< 0.001) with all three locations greater than C (2.77%; P< 0.001). Variance (s2) also differed (A=1.44% B=1.59% C=1.05% D=2.18%; P< 0.05) across chop locations. Of the variability in IMF, 33.0% was attributed to sire line, 10.16% to chop location and 4.01% to sex, with 52.83% unaccounted for. Location A chops were the most tender (2.57kg; P< 0.001) and C chops the least tender (2.93kg; P< 0.01). No differences in variability (s2; P=0.40) of tenderness were observed across chop location (A=0.31kg B=0.24kg C=0.24kg D=0.23kg). In conclusion, chop location, sex, and sire line all contribute to the amount and variability of pork loin marbling. Supported by National Pork Board Grant #18-118.

Relationships Between Loin Color, Cut Thickness, Cooking Method, Water-Holding Capacity and Tenderness for Pork Cooked to 62.8°C

ObjectivesConsumer research has consistently shown that consumers over-cook pork creating a subpar eating experience. In 2011, the USDA/FSIS changed the internal doneness temperature from 71.1 to 62.8°C. However, how tenderness and water-holding capacity is affected in pork chops and roasts differing in thickness and color score cooked to 62.8°C is unknown. Understanding these relationships from chops and roasts cooked to 62.8°C is crucial to the pork industry.Materials and MethodsBoneless and bone-in pork loins were purchased commercially on 3 selection trips to represent the National Pork Board subjective color scores of 2 and 4. The tenderloin was removed from the bone-in loins and randomly assigned to treatments. The sirloin and blade ends were removed, and bone-in ribeye chops were cut to either 1.3, 1.9 or 2.5 cm thick. Twelve chops were cut from each loin with a portion of the rib bone present in each chop. The blade end of the boneless loins was removed, and blade chops were cut to either 1.3, 1.9 or 2.5 cm thick. Three blade ends within color score were used to obtain 12 chops. The boneless center-cut chops were cut to either 1.3, 1.9 or 2.5 cm. Each boneless loin was cut into 12 chops. Boneless loin roasts (0.9 and 1.8 kg roasts) were cut from color score 4 boneless loins. Whole boneless center-cut loin roasts were cut into 2.7 kg roasts from the color score 2 loins. Prior to cooking, drip loss, pH and raw color were determined. Chops were then cooked to 62.8°C either by baking, grilling, pan frying, or pan-sautéing. Roasts were cooked to 62.8°C either by baking or grilling. Internal temperature was monitored by inserting an iron constantan thermocouple into the geometric center of the chop or roast. Cook yield, cook time, tenderness assessed by Warner-Bratzler shear force, and cooked internal color were determined. Each of the 24 treatments for each type of chop (2 colors × 3 thicknesses × 4 cooking methods) and the 8 roast treatments (4 weights × 2 cooking methods) were replicated 20 times.ResultsCooking method and chop thickness affected cook yield and cook time. Baked chops had the longest cooking times and sautéed chops had the highest cook yields (P < 0.05). Grilled chops had the highest (P < 0.05) cook loss. The color score 4 blade and boneless chops were more tender than the color score 2 chops (P < 0.05). However, for bone-in chops, the inverse was reported (P < 0.05). Thickness had minimal effect on tenderness for the boneless chops (P < 0.05). Although bone-in and boneless, baked chops had the longest cooking times, they were the most (P < 0.05) tender. Baked whole boneless roasts had higher cook yield and longer cook times from grilled whole boneless roasts (P < 0.05). For boneless loin roasts (0.9 kg), baked roasts had higher cook yields, longer cook times, were tougher, and had a redder internal cook color than boneless loin roasts that were grilled (P < 0.05). Heavier boneless loin roasts had lower cook yield, longer cook times, and were tougher compared to lighter weight boneless loin roasts (P < 0.05). Baked tenderloins had higher cook yield, longer cook times and were redder in internal color than grilled tenderloin roasts (P < 0.05).ConclusionOverall, this study revealed that color, cooking method, and thickness impacted drip loss, cook yield, cook time, cooked color, and tenderness of blade, boneless, and bone-in chops, tenderloins, and roasts.

Relationships Between Loin Color, Cut Thickness, Cooking Method, Water-Holding Capacity and Tenderness for Pork Cooked to 62.8°C

ObjectivesConsumer research has consistently shown that consumers over-cook pork creating a subpar eating experience. In 2011, the USDA/FSIS changed the internal doneness temperature from 71.1 to 62.8°C. However, how tenderness and water-holding capacity is affected in pork chops and roasts differing in thickness and color score cooked to 62.8°C is unknown. Understanding these relationships from chops and roasts cooked to 62.8°C is crucial to the pork industry.Materials and MethodsBoneless and bone-in pork loins were purchased commercially on 3 selection trips to represent the National Pork Board subjective color scores of 2 and 4. The tenderloin was removed from the bone-in loins and randomly assigned to treatments. The sirloin and blade ends were removed, and bone-in ribeye chops were cut to either 1.3, 1.9 or 2.5 cm thick. Twelve chops were cut from each loin with a portion of the rib bone present in each chop. The blade end of the boneless loins was removed, and blade chops were cut to either 1.3, 1.9 or 2.5 cm thick. Three blade ends within color score were used to obtain 12 chops. The boneless center-cut chops were cut to either 1.3, 1.9 or 2.5 cm. Each boneless loin was cut into 12 chops. Boneless loin roasts (0.9 and 1.8 kg roasts) were cut from color score 4 boneless loins. Whole boneless center-cut loin roasts were cut into 2.7 kg roasts from the color score 2 loins. Prior to cooking, drip loss, pH and raw color were determined. Chops were then cooked to 62.8°C either by baking, grilling, pan frying, or pan-sauteing. Roasts were cooked to 62.8°C either by baking or grilling. Internal temperature was monitored by inserting an iron constantan thermocouple into the geometric center of the chop or roast. Cook yield, cook time, tenderness assessed by Warner-Bratzler shear force, and cooked internal color were determined. Each of the 24 treatments for each type of chop (2 colors × 3 thicknesses × 4 cooking methods) and the 8 roast treatments (4 weights × 2 cooking methods) were replicated 20 times.ResultsCooking method and chop thickness affected cook yield and cook time. Baked chops had the longest cooking times and sauteed chops had the highest cook yields (P < 0.05). Grilled chops had the highest (P < 0.05) cook loss. The color score 4 blade and boneless chops were more tender than the color score 2 chops (P < 0.05). However, for bone-in chops, the inverse was reported (P < 0.05). Thickness had minimal effect on tenderness for the boneless chops (P < 0.05). Although bone-in and boneless, baked chops had the longest cooking times, they were the most (P < 0.05) tender. Baked whole boneless roasts had higher cook yield and longer cook times from grilled whole boneless roasts (P < 0.05). For boneless loin roasts (0.9 kg), baked roasts had higher cook yields, longer cook times, were tougher, and had a redder internal cook color than boneless loin roasts that were grilled (P < 0.05). Heavier boneless loin roasts had lower cook yield, longer cook times, and were tougher compared to lighter weight boneless loin roasts (P < 0.05). Baked tenderloins had higher cook yield, longer cook times and were redder in internal color than grilled tenderloin roasts (P < 0.05).ConclusionOverall, this study revealed that color, cooking method, and thickness impacted drip loss, cook yield, cook time, cooked color, and tenderness of blade, boneless, and bone-in chops, tenderloins, and roasts.

Predicting pork loin chop yield using carcass and loin characteristics

The objective was to determine the predictive ability of carcass length for the number of equal-thickness chops obtained from a boneless pork loin. Longer pork carcasses are assumed to yield longer loins and, therefore, an increased number of chops. Loins were collected from pigs (1,238 total) raised under commercial conditions and marketed when the mean pig weight in a pen reached 138 kg. Pigs were slaughtered over 7 wk in a commercial facility. Carcass length was measured at 1 d postmortem on the left side of each carcass from the anterior edge of the symphysis pubis bone to the anterior edge of the first rib. Carcasses were fabricated, and boneless loins (North American Meat Processors number 414) were vacuum packaged and transported to the University of Illinois Meat Science Laboratory. Loins were stored at 4°C for 14 d. At the end of the aging period, loins were weighed, measured for stretched length (stretched to maximum length without distortion) and compressed length (compressed to minimum length without distortion), and sliced into 2.54-cm-thick chops. Boneless chops were counted and weighed. Carcass length ranged from a minimum of 78.2 cm to a maximum of 96.5 cm and the number of boneless chops ranged from a minimum of 13 to a maximum of 20 chops. Data were analyzed using the regression procedure of SAS. The dependent variable was the number of boneless chops. Coefficient of determination () was calculated for carcass length, boneless loin weight, compressed loin length, and stretched loin length. Carcass length explained 15% ( < 0.0001) of the variation in the number of loin chops. Loin weight explained 33% ( < 0.0001) of the variation in the number of loin chops. Compressed loin length and stretched loin length explained 28 and 8% ( < 0.0001), respectively, of the variation in the number of loin chops. Multiple linear regression was used to determine a predictive equation for the number of loin chops using the stepwise selection option of all independent variables. The combination of boneless loin weight, compressed loin length, 10th-rib carcass fat depth, and carcass length explained 45% of the variation ( < 0.0001; C(p) = 16.76) in the number of loin chops using a required statistic at the SLENTRY and SLSTAY level = 0.15. Overall, carcass length is a poor predictor of the number of equal-thickness loin chops that can be derived from a boneless pork loin.

130 Carcass length is a poor predictor of the number of boneless chops from a pork loin

130 Carcass length is a poor predictor of the number of boneless chops from a pork loin

The effect of skatole and androstenone on consumer response towards fresh pork from m. longissimus thoracis et lumborum and m. semimembranosus

Consumer liking was assessed for boneless chops (m. longissimus thoracis et lumborum) and schnitzels (m. semimembranosus) from castrates and entire male pigs with an androstenone content of up to 9.4ppm and a skatole content of up to 0.92ppm in the back fat. Skatole affected both odour and flavour as assessed by trained sensory panellists (P<0.05–P<0.001), while androstenone particularly affected flavour (P<0.01–P<0.001). Furthermore, the skatole compound seemed to be more important in explaining the presence of boar taint in the chops, while androstenone seemed to be more important for the schnitzels. For the chops, tenderness was the most important attribute for consumer liking independently of both the androstenone and skatole contents (P<0.001). Furthermore, increasing contents of both androstenone (P=0.05) and skatole (P=0.04) resulted in a decreased liking of the chops. Skatole was the most important factor regarding consumer response towards the schnitzels (P=0.03). The very low liking scores for both chops and schnitzels were mainly attributable to the androstenone content.

Effects of high levels of dietary niacin from nicotinic acid on growth and meat quality of finishing pigs raised during summer (2014)

A total of 1,232 pigs (PIC 337 × 1050; initially 59.4 lb) were used in a 98-d study to evaluate the influence of increasing dietary niacin supplementation on growth, body temperatures, and meat quality of pigs raised in a commercial facility during the summer. There were 28 pigs per pen and 11 pens per treatment. Basal diets contained corn, soybean meal, and dried distillers grains with solubles (DDGS). The four dietary treatments were formed by adding increasing levels of nicotinic acid as the source of niacin (Lonza, Allendale, NJ) at 14, 172, 331, and 490 mg/lb of complete feed. On d 57, 58, and 59, rectal temperatures and skin temperatures on the top of the shoulder and rump were collected from 2 pigs per pen (1 barrow and 1 gilt). On d 98, 2 pigs per pen (1 barrow and 1 gilt) were visually selected as the heaviest pigs in the pen and were harvested for carcass and meat quality data. Carcass traits, pH decline, and subjective loin color and marbling scores were measured at a commercial abattoir. Afterward, a 15.7-in. segment of the loin was used for meat quality analysis, including measurements of ultimate pH and purge loss. Boneless chops (1 in. thick) were cut from the loin segment and were used to determine 24-h drip loss, subjective color and marbling, objective lean color values (L*, lightness; a*, redness; and b*, yellowness), and muscle niacin concentrations. Average daily temperatures within the barn ranged from 63.8 to 85.5°F throughout the length of the study, with daily low temperatures from 59.9 to 81.0°F and daily high temperatures from 66.1 to 93.3°F. Overall, temperature was cooler than expected for the facility compared with normal seasonal increases associated with the summer months. Time × day interactions (P < 0.01) were observed for rectal, shoulder, and rump temperatures; however, body temperature was not consistently influenced by dietary niacin concentrations during the collection period. Overall (d 0 to 98), increasing dietary niacin did not influence ADG or F/G, but it tended (linear; P = 0.07) to increase ADFI. Increasing niacin supplementation did not influence carcass traits; however, for meat quality, it did increase (linear; P < 0.01) pH decline at 45 min and 21 h postmortem. Increases (linear; P < 0.05) in a* and b* were observed for chops from pigs fed increasing niacin, but subjective chop color scores were not affected by increasing niacin supplementation. In summary, dietary niacin above the animal’s requirement estimate did not consistently influence rectal or skin temperatures and had negligible influences on growth performance, carcass traits, and meat quality parameters.; Swine Day, Manhattan, KS, November 20, 2014

Effect of distillers dried grains with solubles and ractopamine (Paylean) on quality and shelf-life of fresh pork and bacon

Pigs (n = 240) were allotted in a 5 x 2 factorial arrangement with 5 levels of distillers dried grains with solubles (DDGS): 0, 15, 30, 45, and 60%, and 2 ractopamine (RAC) levels: 0 and 5 mg/kg. Four pigs per pen (2 barrows, 2 gilts) closest to pen mean BW were used for meat quality evaluation. Loins (n = 119) were evaluated for objective color; moisture and fat; subjective color, marbling, and firmness; and drip loss. Bellies (n = 119) were evaluated for weight, length, width, thickness, objective fat color, and firmness. Cured bellies were evaluated for pump yield, cook loss, and sliced bacon cook loss. Loin thiobarbituric acid reactive substances (TBARS) were evaluated on enhanced (salt and phosphate) boneless chops held in modified atmosphere (80% O(2)/20% CO(2)) packages for 0, 7, 14, and 21 d. Bacon TBARS were evaluated on sliced bacon held in vacuum packages for 0, 28, 56, and 84 d. Fat samples were collected from each jowl and belly and evaluated for fatty acid profile and iodine value (IV). Increasing DDGS decreased subjective marbling (P = 0.0134) and firmness (P = 0.0235), and increased drip loss (P = 0.0046). Distillers dried grains with solubles did not affect loin pH, subjective or objective color, percent moisture, or percent fat (P > 0.05). The RAC decreased subjective color (P = 0.0239), marbling (P = 0.0445), and a* (P = 0.0355). Increasing DDGS decreased belly weight (P = 0.0155), length (P = 0.0008), thickness (P = 0.0019), and firmness (P = 0.0054); decreased belly fat L* (P = 0.0818); and increased belly cook loss (P = 0.0890). Ractopamine did not affect any belly measurements, and there were no DDGS x RAC interactions (P > 0.05). Distillers dried grains with solubles did not affect loin TBARS at 0, 7, or 14 d. At 21 d, loin TBARS from 30, 45, and 60% DDGS groups were increased compared with 0 and 15% groups (P < 0.05). Ractopamine did not affect (P > 0.05) loin TBARS, and there were no (P > 0.05) DDGS x RAC interactions. Distillers dried grains with solubles and RAC did not affect bacon TBARS (P > 0.05). Increasing DDGS increased belly (P = 0.0207) and jowl (P < 0.0001) IV, and decreased MUFA:PUFA in belly (P < 0.0001) and jowl (P < 0.0001) fat. Ratio of SFA:unsaturated fatty acids decreased in jowl (P = 0.0002) and belly fat (P = 0.2815). Ractopamine did not affect fatty acid profiles or IV, and there were no DDGS x RAC interactions (P > 0.05). Results indicate that increased DDGS have minimal effects on loin quality, but decrease belly quality, bacon processing characteristics, and fat stability. Ractopamine does not negatively affect these characteristics and does not interact with DDGS.

Validation of Time and Temperature Values as Critical Limits for Salmonella and Background Flora Growth during the Production of Fresh Ground and Boneless Pork Products

To provide pork processors with valuable data to validate the critical limits set for temperature during pork fabrication and grinding, a study was conducted to determine the growth of Salmonella serotypes and background flora at various temperatures. Growth of Salmonella Typhimurium and Salmonella Enteritidis and of background flora was monitored in ground pork and boneless pork chops held at various temperatures to determine growth patterns. Case-ready modified atmosphere packaged ground pork and fresh whole pork loins were obtained locally. Boneless chops and ground pork were inoculated with a cocktail mixture of streptomycin-resistant Salmonella to facilitate recovery in the presence of background flora. Samples were held at 4.4, 7.2C, and 10°C and at room temperature (22.2 to 23.3°C) to mimic typical processing and holding temperatures observed in pork processing environments. Salmonella counts were determined at regular intervals over 12 and 72 h for both room and refrigeration temperatures. No significant growth of Salmonella (P < 0.05) was observed in boneless pork chops held at refrigeration temperatures. However, Salmonella in boneless pork chops held at room temperature had grown significantly by 8 h. Salmonella grew at faster rates in ground pork. Significant growth was observed at 6, 24, and 72 h when samples were held at room temperature, 10°C, and 7.2°C, respectively. No significant growth was observed at 4.4°C. Background flora in ground pork samples increased significantly after 10 h at room temperature and after 12 h for samples held at 10 and 7.2°C. Background flora in samples held at refrigeration temperatures did not increase until 72 h. Background flora in the boneless chops increased significantly after 6 h at room temperature and after 24 h when held at 10 and 4.4°C. These results illustrate that meat processors can utilize a variety of time and temperature combinations as critical limits to minimize Salmonella growth during production and storage of raw pork products.

Color and Oxidative Rancidity of Gamma and Electron Beam‐Irradiated Boneless Pork Chops

ABSTRACTColor and oxidative rancidity were determined for chilled (3 ± 2°C) and frozen (−17 ± 3°C) boneless pork chops packaged in vacuum or air and irradiated to an absorbed dose of 0, 1.5 or 2.5 kGy (chilled) or 0, 2.5 or 3.85 kGy (frozen) of electron beam or cobalt60 irradiation. Irradiation of vacuum‐packaged chops produced redder, more stable (color and rancidity) product. More pronounced oxidative rancidity and less stable display color were noted for samples irradiated in aerobic packaging. Irradiation source had varying but limited effects on color and rancidity. Optimum packaging conditions can control color and rancidity changes in boneless chops, thereby enabling irradiation to be a useful intervention technology.

Prediction of Grilled Boneless Pork Chop Quality

LEARNING OUTCOME: To understand the relationships between grill temperature and grilled boneless pork chop quality.Foodservice units play major roles in maintaining the quality of meat served to consumers. A randomized complete block experimental design with five replications (blocks) was used to evaluate the effects of equipment temperature (ET) {93, 121, 148, 176, 204°C} on grilled boneless pork chop quality. Regression analysis using stepwise selection was used to determine significant (P< 0.05) response relationships and to develop predictive equations (linear, quadratic, cubic, quartic) for yield (%), cooking time (min/g), sensory quality (juiciness, tenderness), and Hunter external (HE) and internal (HI) cooked chop color. One inch thick boneless chops were cut from Canadian Backs (NAMP 414), frozen and held at -10°C for no more than six weeks. Chops were tempered (3°C) for 24 hours prior to grilling to a final internal temperature of 71°C. Initial internal temperatures (ITT) were recorded. Juiciness and tenderness were evaluated by a consumer panel using an eight point rating scale (8=Very juicy, tender; l=Very dry, tough). The quartic response for yield (%) was influenced by ET and HT. An ET of 121°C produced the highest yield (78.3%) while an ET of 204°C resulted in the lowest yield (76.0%). Cooking time (linear) was 0.21min/g for chops grilled at 93°C while cooking time was 0.11min/g for chops grilled at 204°C. No significant relationships were found for sensory quality. Linear relationships were observed for HI color. HI cooked chop color, redness (Hunter “a”) values, decreased when chops were cooked at higher ET. As ET increased, HI “L” values decreased indicating a darker, more gray interior color when compared to the lighter, whiter interior color of chops cooked at 93°C. Mean HI “b” values increased from 7.3 at 93°C to 10.48 at an ET of 204°C. Reducing ET increases yield and impacts internal cooked color but does not influence sensory quality. While reducing ET will increase yield, further investigation is needed to understand the influence of IIT on yield.

EFFECTS OF EXTERNAL FAT COVER, BONE REMOVAL AND ENDPOINT COOKING TEMPERATURE ON SENSORY ATTRIBUTES AND COMPOSITION OF PORK CENTER LOIN CHOPS AND ROASTS

ABSTRACT.Effects of fat cover, bone removal and endpoint cooking temperature on proximate and sensory characteristics of pork center loin chops were investigated. Only brown color of broiled chops was affected by presence of bone and by endpoint temperature. Fat cover only affected perceived chewiness of chops. Broiled boneless chops contained higher percent fat than bone‐in chops. There were no differences in protein, fat or moisture percentages in cooked chops due to fat cover. Higher internal temperature decreased percent moisture and increased percent protein. Percent fat did not differ due to internal temperature. A consumer study to determine the degree of liking of pork center loin roasts showed that consumers preferred roasts with no fat cover more than roasts with 0.6 cm fat cover and roasts cooked to 71.1°C compared to roasts cooked to 76.7°C. There was no difference in preference between boneless and bone‐in roasts.